About The Dictionary
Our Dictionary has been devised to provide you with fundamental knowledge of the materials and the production techniques we utilize to create our products. Additionally, we have clarified some of the general terms we use throughout the site.
We’d love to hear from you regarding any additions or improvements you may have for us.
Thank You and please enjoy!
Abalone, a type of Mother of Pearl, is also known as the 'Paua Shell'. For centuries the Maori tribes of New Zealand have used Abalone for mystical carvings and jewellery. This Mollusks shell has been referred to as 'Sea Opal' because of its colourful resemblance to the Opal.
A type of thermoplastic that comes in many colours and various levels of transparency.
No stone is more creatively striped by nature than Agate. It is a very common stone often used in jewellery. It's found in a wide range of colours including black, grey, brown, yellow, pink and blue. Agate is a porous stone and can be dyed to enhance the colour. In ancient times the stone is said to have had the power to quench the thirst and protect against fever. The mining of agate was documented as early as the 1490's in Germany; the stone is also mined in South America. Agate has a Mohs hardnessrating of 7.
The Alexandrite is a mineral that changes colour dependant on whether it is viewed in natural or artificial light. Alexandrite can appear red in candle light and blue/green when in fluorescent light. The stone was first discovered in 1834. The largest stones are mined mainly in Burma and Rhodesia and can weigh up to 30 carats (6.0g). However the higher quality stones are found in the Ural Mountains, Russia. Alexandrite has a Mohs hardnessrating of 8.5.
Amber is an ancient and valuable stone which is sourced from fossilized tree resin, (conifer/pine trees). It is also a natural hydrocarbon that comes in many colours ranging from yellow to brown to blue. In the past, it was thought that Amber possessed magical powers and protected the wearer from evil. Due to the nature of the source amber can sometimes contain small insects. The two main sources of Amber today are The Baltic's and the Dominican republic. Amber has a Mohs hardnessscale rating of 2.5.
Amethyst is the most striking member of the crystal quartz family. It's usually purple in colour, however crystals have been know to have a colour range of milky white to a very pale lavender. The ancient Greeks believed it to have the power to make the wearer immune to the affects of alcohol. Large deposits of the stone have been found in Brazil and neighbouring Uruguay. Another major source is Madagascar. Other countries known for having deposits of the stone are Canada, Tibet and Sri Lanka. Amethyst has a Mohs hardnessrating of 7.
Apatite is a clear to opaque stone that comes in many colours including violet, blue, yellow and green. This stone is rarely used in jewellery because it is too brittle and soft. The major sources of Apatite are Brazil, Burma and Mexico. Other known sources are Germany, India, Norway and Spain. Apatite has a Mohs hardnessrating of 5.
This is the effect of light rays forming a star on the surface of certain types of stones. Asterism is created by the reflection of light from thin, fibrous or needle-like occlusion of the gemstone. Sapphire and Ruby Cabochanscan show effective six-rayed stars while some other gems can produce 4-rayed stars. 12 rayed-stars are very rare.
Aquamarine got its name from its seawater-like colour which, in Latin, translates to 'Water of the Sea'. Aquamarine is a cousin of the Emerald, as they both belong to the Beryl family of stones. This beautiful stone can be found in many countries: Australia, Burma, China, and Zimbabwe to name a few. The largest Aquamarine stone has been found in Brazil weighing over 100kgs. The Mohs hardnessrating for Aquamarine is 7.5-8
Aventurine can also be referred to as 'goldstone' and it is part of the quartz family. In its most common form, Aventurine is green. However it can be orange, blue, yellow or even grey. The stone has high mineral content and can have a glistening effect. Aventurine has a Mohs hardness ratingof 6.5
Azurite is a copper based mineral that is often used in jewellery. Its colour ranges from very dark green to very light blue. There are many sources of the stone and it can be found in the USA, Southwest Australia, Zambia, Morocco and Mexico. The Mohs hardness rating for the stone is 3.7- 3.9
A bail is a metal component that usually attaches the pendant to a chain or cord.
Base metals are non-precious metals that will corrode or oxidise very easily. Copper, zinc, tin and lead are the main base metals used in the production of jewellery.
Beads are small objects, usually made from glass, stone, wood, plastic, seeds, or ceramic. Each bead has a hole on either end to pass the string/cord through in order to make a necklace or bracelet.
The Beryl family comprises several stones (Aquamarine, Emerald and Morganite) that each have their own unique colour yet share the same properties. These typical hexagon beryl crystals are mainly found in gemstone deposits in South America and Western Africa. They also occur in Russia, Ukraine and the USA. The Mohs hardnessrating for beryl is 7.5-8.
The Modern Birthstone chart is the official birthstone list from the American National Association of Jewelers, Jewelers of America, adopted officially in 1912. In October 2002, this list was updated to include Tanzanitefor December's birthstone by the American Gem Trade Assoc. (AGTA).
January - Garnet
February - Amethyst
March - Aquamarine
April - Diamond
May - Emerald
June - Alexandrite
July - Ruby
August - Peridot
September - Sapphire
October - Opal
November - Topaz or Citrine
December - Turquoise Tanzanite, or Blue Zircon
Bloodstone is an opaque Chalcedony with red spots. The spots in the stone are caused by iron oxide. An old name for bloodstone that is still used in parts of Europe is 'Heliotrope'. It is mainly used for ornamental objects. The most notable deposits are in India while other known sources are Australia, Brazil, China and the USA. Bloodstone has a Mohs hardnessrate of 6.5 to 7
Cabochon describes a gemstone that has been domed and highly polished as opposed to faceted. Cutting and polishing in this way is usually applied to opaque stones, while faceting a gem would normally apply to a transparent stone. The softness of the stone has to be taken into account as any stone with Mohs hardnessRating of less than 7 is too soft to be formed as a cabochon because it will scratch too easily.
Cameo is a method of carving a gemstone or shell, where the design is raised above a background of a different colour. The 3 materials that are usually used in this process are shell, glass and Agate.
Carat is the standard measure of weight used for gemstones. One carat is equivalant to 0.2 gram and a hundredth of a carat is called a 'point'. This unit of weight was introduced in 1907.
Carnelian, also known as cornelian or carneole, is probably named after the Kornel Cherry because of its brownish red-orange colour. Carnelian can be translucent to opaque. The highest quality Carnelian is sourced in India, Brazil and Uruguay. Carnelian has a Mohs hardnessrating of 7.
Chalcedony is a family of minerals (cryptocrystalline quartz) that are often milky to greyish to blue. This large family of stones includes: Agate, Onyx, Carnelian, Bloodstone and Jasper - to name a few. Chalcedony is a porous and translucent stone that has a Mohs hardnessrating of between 6 and 7.
A choker is a type of necklace that fits tightly around the neck. Chokers vary in size with standard lengths between 14" and 16".
Chryscolla (meaning 'golden lime' in Greek) has an aesthetic blue/green colour. This mineral has been used in ornaments for years and years however it was only classified as a mineral in 1968. It forms in the oxidised zones of copper found in the earth's crust. Notable deposits have been found in the USA, Russia, Chile and the Congo. Chryscolla Mohs hardnessrating varies from 2-4.
An apple green coloured gemstone from the Chalcedony family. The best known sources of Chrysoprase are Queensland, Western Australia, Germany, Poland, Russia, Arizona, California, and Brazil. Chrysoprase has a Mohs hardnessrating is 6-7.
Coral, also know as Precious coral, is an organic gemstone. The distinguishing features of precious coral are its durability and intensely coloured skeleton . The coral typically grows on rocky sea beds at depths of between 10-300m in areas around Japan, Taiwan and near the straights of Gibralter. Coral has a Mohs hardnessrating of 3.5
Corundum is named by its colour. Red corundum is called 'Ruby' and blue corundum is called 'Sapphire'. In its most rare and pure form, Corundum is colourless and called 'White Sapphire'. The mining of the stone takes place in different parts of the world depending upon its final use. Corundum is mined in many countries around the world including Thailand, Sri Lanka and Australia. Corundum is a very hard mineral with a Mohs hardness rating of 9, only Diamondsare harder.
Crystal is high quality glass containing at least 10% lead oxide. Lead is added to the melting process to produce a very clear glass that resembles Rock Crystal. The process of making lead crystal was discovered by the English glassmaker George Ravenscroft in 1676. Crystal is coloured by adding various metal oxides during the melting process.
Long ago pearls were seen as a financial investment alongside property and artwork. They were so rare because they were created by chance in the sea. Today, however, Pearls are created artificially by placing shell beads into the oyster which is then placed back in the sea for several years. Most of the cultured pearls today are created in Japan in the warm waters of the South Pacific. Tahitian Black pearls are created from larger oysters and freshwater pearls are created inside mussels from China. This method of creating pearls was invented in 1893 by Kokichi Mikimoto. Pearls have a Mohs hardnessrating of 3.
A very inexpensive stone that is created in laboratories and used as a cheaper alternative to Diamonds. They were first developed back in 1977. When created, the stone is usually optically flawless with no colours. However, colours can be added during the forming process with chemicals. The Mohs hardnessrating for CZ is 8.
There are three types of cuts that can be applied to gemstones, The Faceted, The Plain and the Mixed Cut.
The FacetedCut is applied mostly to transparent Gemstones.
The Plain Cut, know also as Cabochan (no facets) where the surface is smooth and even with a very high polish. This type of cut is used on Opaquegemstones.
The Mixed cut is a combination of the previous two cuts, the upper part of the gemstone will be facetedand the lower part of the stone will be smooth or vice versa.
Diamonds get their name from the Greek word 'adamas' which translates to 'The Unconquerable'. Diamonds are very precious and optically very beautiful. Due to its visual beauty and hardness the Diamond is regarded as the 'King of Gemstones'.
Diamonds are formed from carbon (basically coal) that crystallises under immense pressure over a very long period of time. Until the 1800's, diamonds were only found washed out of diamondiferous places (volcanic pipes that release the Diamond bearing rock out into the earth's natural environment).
The most famous pipe in South Africa is the Kimberly Mine where mining was discontinued in 1914. Today, Australia leads the way in Diamond production closely followed by China and Russia.
There are a number of famous Diamonds which have been defined by their size and beauty, to name a few:
The Dresden was a green diamond from India which weighed 41 carats.
The Star of Africa weighed a massive 530.20 carats and was cut from the largest rough diamond ever found; it weighed in at 3106 carats. This stone is now kept in the Tower of London.
A Diamond's value is decided by the four C's: Carat, Clarity, Colour and Cut. Diamonds are found in many colours - mostly a yellowish colour until given various treatments. The rare colours are green, red, blue, and purple. These are known as 'fancy colours'. These stones are very valuable and have been known to fetch collector's prices. The inner perfection of a diamond is measured by Clarity. Polished diamonds without any occlusions under 10X magnification are considered flawless.
There are many types of cuts for Diamonds both new and old with The Brilliant Cut and The Princess Cut to be the most common. Some older cuts are the Point Cut, the Old European Cut, and the Peruzzi Cut. Carat is the unit of weight that is used to weigh the stone. Diamonds are the hardest gemstone on the Mohs hardnesswith a score of 10.
Diopside comes in two varieties: Black Star and Chrome. Diopside has several drawbacks in that it's only available in small sizes and when the stone does come in larger size the colour is too deep and dark. Major sources are found in Siberia, Yakutia, Canada and South Africa. Diopside has a Mohs hardnessrating of 5.5 û 6.5.
Electroform / Electroplate
Electroform is a special production technique that results in hollow jewelry or artefacts.
During this process a wax model is placed into a plating bath which uses electricity to deposit the metal on to the outer surface of the wax model. Once the plating process is complete the wax is then removed, the result: a hollow item which compared with its overall size is very lightweight.
This technique is mainly used to create large and bold items, which would be impossible or too expensive to create through other production techniques, such as casting.
The name Emerald derives from the Greek word Smaragdos which literally means 'Green Stone'. Emerald is the most precious stone in the Beryl family which includes Aquamarine, Golden Beryl and Morganite. The finest specimens of Emerald are clouded by occlusions. These are not necessarily faults in the stone as they can be used to prove that the stone is genuine. These occlusions are referred to by experts as jardin.
Significant deposits of Emerald are found in Columbia, however only a third of the stones from the Columbian deposits are worth cutting. Good quality specimens have been mined in Zimbabwe where the crystals are small but of a gemstone standard. Other known deposits of Emeralds can be found in Brazil, Afghanistan, India, Ghana and Zambia to name a few.
Emeralds have a Mohs hardnessrating of between 7- 8.
A vitreous Enamel surface is achieved by fusing glass particles to sheet metal or cast iron and firing it at temperatures in excess of 800°C. This results in a surface that is incredibly hard-wearing to all the elements. It is temperature resistant (up to 800°C) and chemical resistant with exceptional colour stability. The finished enamelled product is easy to maintain, and to keep clean. Therefore, it can be used for many applications internally and externally. Natural Enamel is very expensive which is why most of today's Enamel is synthetic.
An extender chain is a small length of chain (usually around 2"-3" long) which is added to an existing chain to provide extra length if required.
A flat surface cut or polished into a gemstone is known as a facet. These flat surfaces are created on gemstones to enhance the overall appearance and beauty of the stone.
Faceting the perfect angles is vital and a very crucial part of making the stone more reflective because light reflection is how a gemstone brings out its individuality and its inner beauty. There are many types of cuts in use today from round, oval, cone-shaped, square, rectangular, triangular to multi- cornered odd shapes. In addition, there are some very cute shapes such as pear-drop, barrel and heart-shape.
Filigree is gold or silverwire that has been twisted into patterns and then soldered to create different types of jewellery. This kind of jewellery production method dates back to the Egyptian Pharaohs.
Findings are a range of components that are used in jewellery production or as jewellery parts, such as; bracelet clasps, earring hooks, earring backs, jump rings and link locks to name a few.
The fineness of a precious metal i.e. Gold or silverrefers to the ratio of the primary metal when alloyed with other metals.
This is for all those people who thought Garnets were redà Garnet is a group of stones which includes around 20 different variations, such as; Andradite, Hessonite and Rhodalite - to name a few. Garnets have a wide range of colours and the only colour that they don't appear in is Blue. A Garnet's Mohs hardnessis between 6 and 8.
Gold is a highly sought after precious metal which has been used since prehistoric times for making jewelry, coins and ornaments. The purity of gold is measured in Karats:
Pure gold (24K) is very, very soft - One gram nugget of pure gold can be hammered into a sheet one meter square.
Due to the softness of the metal, when it's used for jewellery production it has to be alloyed with other metals. This, therefore, alters the hardness, durability, colour and various other properties of the gold. For example, to create Rose Gold, 25% copper is added to the melt with 18k gold. White gold is created when either nickel or palladium are added to the alloy. Blue Gold is created by mixing gold with iron and Purple Gold gets its colour from mixing gold with aluminium, Blue Gold is very brittle and is only used in very specialised production techniques. Gold today has many more uses; food, drink, medicine, and electronics to name just a few.
South Africa leads the way in gold extraction. In the 1800's, the country produced around 50% of the world's total output. In the late 1900's it was up to 79%. This number has since declined, mainly due to the difficulties extracting the metal. Since 2007, China leads the way in gold output.
Gold plating is a process that applies a layer of gold to a surface of another metal, usually silveror copper, to give it a brighter, lasting finish. However, over time and due to the chemical reaction between the metals tarnish will occur and the thickness of the gold layer and the quality of the process will influence the time span of the layer resisting tarnish.
Gold plating can be carried out with most forms of gold alloy.
Please see Vermeilfor more details.
Gold Filled Jewellery
Can also be referred to as ôRolled Goldö This technique comprises of a solid gold layer bonded with heat and pressure on to a base metal such as brass. This can give the base metal the look and luster of 14K quality gold. The length of time the metal sustains its finish depends on the jeweller and can last up to 30 years if the work is by a qualify technician.
Hallmarks are official or standard stamps that are applied to precious metals and used for various purposes. Mainly, Hallmarks are used to indicate the metal's fineness*, while additional hallmarks are used to identify the sponsors/manufacturers and in some countries identify the assay office** that stamped the product to prove its authenticity.
*An example of a Sterling Silver hallmark would be the numbers '925' which means '925 parts to 1000'. In layman's term its 92.5% pure silver.
** In the UK, for example, it is illegal to distribute products which have not been hallmarked by the local assay office.
A member of the Garnet family, Hessonite is also known as the 'Cinnamon Stone' due to its cinnamon-brown to orange colour. This is a transparent stone which has deposits in the USA, Brazil, Canada, Madagascar and Sri Lanka. Hessonite's Mohs hardnessrating is between 6.5 and 7.
Howlite, also referred to as 'snow white' is a very soft mineral which is white to grey in colour and occasionally has black veins running through it. Howlite is usually dyed to create imitation Turquoise. Howlite gets its name from the geologist who discovered it, Henry How. Howlite has a Mohs hardnessrating of 3.5.
Hoop earrings got their name from the hoola hoop to describe their round shape, yet, these days hoop earrings can be oval, elongated or even square.
An iridescent object, such as moon stone, is an object that can display a change of colours when the light or angle-of-view changes. Another example of an iridescent object would be an abalone shell.
Iolite, which means 'violet stone' is also known as 'water sapphire' or 'lynx sapphire'. It is a stone that displays many colours, from violet-blue to light blue to yellow-grey colour.
Iolite has sometimes been used as an inexpensive substitute for Sapphire due to its low price tag and availability. It has been mined in many countries including Brazil, Burma, Canada and India to name a few. Iolite has a Mohs hardnessrating of 7-7.5 .
Jade is a semi-precious stone that has a wide range of colours from green to black to white to brown. translucent Jade is more sought after and valuable than opaqueJade. Stones with imperfections are usually used for carving.
For thousands of years the Chinese have regarded Jade to possess medicinal properties.
There are two different minerals that are known as jade: Jadeite and Nephrite. Jadeite is the harder of the two mineralsand is more often used in jewellery. It can be mined in China, Russia and Guatemala, however, the most sought after stones come from Burma, now known as Myanmar.
Nephrite is slightly softer and is often used for carving bowls and vases.
Nephrite has been sourced in China, New Zealand, Russia, Guatemala and the Swiss Alps. There is also the Dark green Jade, know as Canada Jade, which is found in Western Canada. Jadeite can be Jade's Mohs hardnessrating is 6.5-7.
Jasper's name is derived from the Greek meaning 'The Spotted One'. Jasper is a very common stone which is opaquein appearance. It has many colours and patterns. Sometimes it has been known to have a panoramic pattern similar to that of a landscape. There are many varieties of Jasper, Agate-Jasper which is yellow to brown in colour. Egyptian Jasper is also known as a 'Nile Pebble' which has a strong yellow and red colour. Basanite, which has a fine grain, is black in colour.
The stone has been discovered all over the world including Egypt, Brazil, India and Canada.
Jasper has a Mohs hardnessrating of between 6.5 and 7.
Jet is also known as gagate. Jet is fossilised coal which is hard and very lightweight. Genuine Jet is warm to the touch and can be distinguished from synthetic Jet which is usually made from black glass or plastic.
Jet has been mined in Whitby in UK for many many years, believed to be as far back as prehistoric times. It has also been mined in Russia, Germany, France and Spain; however these sources are said to be inferior to the one in the UK. The Mohs hardnessrating is 2.5 to 4 .
Karat (kt / K) is how we measure gold for it's purity. Below is a table showing how pure the gold is at each level.
Karat Percent Gold
24 Kt. 100% Gold
18 Kt. 75% Gold
14 Kt. 58.3% Gold
12 Kt. 50% Gold
10 Kt. 41.7%
Kyanite can have a colour range from the deepest-darkest sapphire blue to green, from grey to white. The stoneÆs colour can sometimes be cloudy and very streaky.
It can be found in many countries around the world such as Brazil, Burma, Kenya, India and Australia.
Its hardness rating depends on the way its scratched. This is because the crystals in Kyanite are long and thin this can also affect the cutting of the stone. Kyanite has a Mohs hardnessrating of between 4.5 and 6.5.
Labradorite is an opaque mineral that displays splashes of many colours after the polishing process. The darker variety of the stone is called Black Moonstone; it's usually cut flat to highlight the brilliant colour within. It was discovered in Canada in a place called 'Paul's Island' near the town of Nain, Labrador. Labradorite has a Mohs hardnessrating of between 6 and 6.5.
Lapis Lazuri is a very rich blue colour. This semi precious stone is made from rock, not mineral. The stone is porous and quite soft and scratches very easily. Because of this, if Lapis is left in water too long it will dull the sheen. Lapis is regarded by many people around the world as the stone of friendship. It has been mined in Afghanistan for over 6,000 years. Chile is said to have extracted lapis of a quality that can compete to that of AfghanistanÆs. Lapis Lazuri has a Mohs hardnessrating of 5.5
A lariat is an open-ended necklace which either looped into a knot or used with a slide knot.
Lever Black is an old style earring clasp that has once again become fashionable.
Malachite is an opaque semi-precious stone with very deep and light green layers, sometimes with thick veins of black running right through it. Malachite is often coated in a colourless wax, oil or hardening agent to enhance appearance and increase durability. The main source for Malachite is the copper mines of the Democratic Republic of Congo, Zambia, Mexico, New South Wales, Israel and Australia. In Israel, Malachite is mined in the Timna Valley which is also known as King Solomon's mines.
Malachite has a Mohs hardnessrating of 3.5 - 4.
Marcasite ('fool's gold') is a mineral that is sometimes referred to as 'white iron pyrite'. It can often be mistaken for Pyrite, but Marcasite is lighter in colour and more brittle. One famous source of Marcasite is Dover in the UK. Marcasite has a Mohs hardnessrating of 6- 6.5.
A mineral is a solid material which is formed as a result of a naturally occurring geological process in the earth's crust. To be classified as a mineral it must be solid and posses a crystal structure. A good example of a crystal mineral is a Diamond. The physical hardness of a mineral is measured according to the Mohsscale.
Morganite is a member of the Berylfamily. Its colour ranges from pale pink to a hint of Orange. Inferior qualities of the stone can be improved by heating them to 4000°C.
The main deposits of Morganite are in Brazil, Madagascar, Afghanistan and California. It was named after the financier and mineral collector John Piermont Morgan. Morganite has a Mohs hardnessrating of 7.5 - 8
In the case of minerals and Gemstones, hardness refers first to scratch hardness then to cutting resistance of each mineral. Friedrich Mohs introduced the term 'Scratch Hardness'. The following table shows the scale that he developed which is still in use today.
Ruby, Sapphire 9
Spinel, Topaz 8
Aquamarine, Emerald 7-8
Amethyst, Chalcedony, Quartz, 7
Steel (pocket knife) 7
Lapis lazuli 5-5.5
Bronze, Coral, Pearl 3
Amber, Fingernail, Ivory,
Shell, Jet 2.5
The word Mollusk describes many varieties of Shell Fish, some of which can naturally produce Pearls and the Mother of PearlShell.
Moonstone is a semi-translucent stone, which can appear in several colours. It is usually whitish- blue; however it can be found in grey, orange, and red and sometimes even appear with no colour at all. Deposits of Moonstone can be found in the following countries; Mexico, Tanzania, Myanmar, Madagascar and Sri Lanka. It can also be found in the USA, specifically Pennsylvania and Virginia. The stones of the best quality are found in Sri Lanka. Labradorite and Albite are rare forms of the stone. Moonstone has a Mohs hardnessrating of 6.
Mother of Pearl
'Nacre' is another name for Mother of Pearl. Mother of Pearl is an organic material produced by some Mollusks on the inner layer of their shells. This material is very strong, resilient and iridescent. It has many uses from jewelry to pistol handles. The main sources of Mother of Pearl are the warmer waters of Asia. The freshwater water variety can be found in many rivers across the USA, Europe and Asia. Mother of Pearl has a Mohs hardnessrating of 3.
A necklace is a piece of jewelry worn around the neck. Necklaces of different lengths have different names: A choker is 14" to 16" long; a princess necklace is 18" long, a matinee necklace is 22" to 23" long, opera is 30" to 35" long, and a rope is over 40" long.
Nephrite is an ornamental stone that can be used in carvings, beads and cabochon cut gemstones. It can be found in many colours; Blacks, reds, pinks, violets. Nephrite jade was once believed to be a cure for kidney stones and was used pre 1800 by the Chinese. It can be located in New Zealand other deposits are in Australia, Brazil, China, Canada, Russia, and Zimbabwe. Nephrite has a Mohs hardnessrating of 6 to 6.5.
Obsidian was named after the Roman, Obsius. It has also been referred to as 'Apache Tears'. Obsidian is volcanic glass that is usually black in colour; however it can also form in red, brown, grey and even green - which is very rare. This glass-like lustrous mineral forms in fiery volcanic rock lava flow. Obsidian can form in very large sizes. It has a Mohs hardnessrating of 5.
Onyx comes from the same Greek word which translates to nail or claw. Onyx is a member of the Chalcedony quartz family. Its colour is usually black or white. This stone was very popular with the ancient Greeks and Romans. Onyx has a Mohs hardnessrating of 7.
The word opal derives from the Sanskrit word ôupalaö which means 'Valuable Stone'. Opals are divided into 3 subgroups: Precious Opals, Fire Opals and Common Opals. Their physical properties vary considerably. Precious Opal's special characteristics are its play of colour. It displays rainbow-like colours that can be seen right through the stone - especially in round cut stones. Types of Precious Opals are as follows: White Opal, Black Opal, Opal Matrix, Boulder Opal, Harlequin Opal, Jelly Opal and Crystal Opal.
Fire Opal, named after its orange colour, is usually milky in appearance. However, its best qualities can be clear and transparent which are suitable for faceting.
Common Opal is opaque and rarely translucent. It shows no play in the colour and has a wide range of trade names: Agate Opal, Angel Skin Opal, Wood Opal, Honey Opal, Hyalite, Hydrophane, Porcelain Opal, Moss Opal, Girasol, Prase Opal, and Wax Opal.
In order to display the stone's best qualities, it must be polished and cut in to round or oval cabochans. Opal has a high water content; sometimes as high as 10%. If the stone becomes dry, it can become brittle and cracks may start to appear. The colour will also appear to fade. For this reason, Opal must be worn by the owner as often as possible so the stone will receive the required amount of air and humidity. The best way to store Opal is to place it in damp cotton wool.
Almost 95% of the world's Precious Opal originates from Australia. Deposits of Fire Opal can be found in Brazil, Mexico, Guatemala and the USA. The Mohs hardnessrating for Opal is 5.5 to 6.5.
Opaque means blocking the passage of light as opposed to translucentor transparent.
This blackening of certain metals is a natural chemical reaction and occurs when exposed to oxygen. This effect can also be induced by chemicals.
A pavè setting is where small stones are set as close as possible, so that the piece literally looks like it has been 'paved' with stones.
There are many types of pearls, including natural pearls, (made with no human interference), Cultured Pearls, pearls made by inserting a small piece of foreign tissue living oyster or Mollusk. Baroque pearls, irregularly- shaped pearls, freshwater pearls, seed pearls and Biwa pearls are pearls that are formed in the freshwater mussel. The Mohs hardnessrating for a pearl is 3.
A pendant is an ornament that usually hangs from a chain/collar/cord which is worn around the neck. Pendants can be made from many different materials: from Diamondsto plastic.
Pewter is a metal alloy that is composed mostly of tin and combined with lead, antimony, bismuth, copper, and/or silver: the formulation varies quite a bit. When pewter is polished it has a silvery luster. Pewter is a soft alloy, with over 90% tin content.
Peridot can also be referred to as 'Olivine' it has a vivid green colour which is a perfect colour to be worn in the summer months. This stone can be found in abundant quantities in Pakistan and Afghanistan. The largest cut Peridot weighed 319 carats and was found on the Island of Zabargad. Peridot has Mohs hardnessrating of 6.5 .
Platinum is a white coloured precious metal that is very strong and dense. Jewellery made from Platinum is usually 90-95% pure metal. Platinum is 60% heavier than gold, it wasn't discovered until the 1700's in Russia. To increase the strength and workability of the metal it is alloyed with Ruthenium, Palladium, Iridium and Osmium which are all members of the Platinum family.
A porous material is a solid object filled with pores or gaps. These gaps can become filled with either a liquid or a gas. There are many examples of porous materials in the world today; bones, cement and foam to name just a few. Porous Gemstones can be injected with colour to give them a more vibrant colourful finish.
A Quadrillion cut stone is square cut stone. This fancy cut is relatively new and is also known as a Princess or Squarillion cut.
Quartz is a crystalline mineral that comes in many forms, including Amethyst, Aventurine, Citrine, Opal, Rock Crystal, Tiger's Eye, Rose Quartz, with many others under the heading Quartz. Rutilated Quartz and Tourmalinated Quartz have needle-like occlusions of other minerals. These occlusions can enhance the appearance dramatically. This common mineral is found right around the globe. From Brazil to India, California to South Africa. Quartz has a Mohs hardnessrating of 7.0 .
Rhinestones are highly reflective glass pieces cut and polished (faceted) to imitate gemstones. The original rhinestones were quartz stones (rock crystal). The best made rhinestones today are formed from highly reflective leaded glass which is cut and polished. Rhinestones were initially sourced from the Rhine River. Rock crystal has Mohs hardnessrating of 7.
Rhodium is a white precious metal that is quite expensive. Rhodium is often used in the plating of base & precious metals to give it a Platinum-like sheen. The main source of this alloy is South Africa.
Rhodolite (which means 'Rose Stone' in Greek), is a member of the Garnet family. It has a colour range from purple-red to pink-red. The main deposits of the stone are Sri Lanka, Zimbabwe, Kenya and the USA. Rhodolite has a Mohs hardnessrating of 7 to 7.5.
Named after the Greek word for rose, it is a reddish-pink colour with thin veins or patches of gray to black. In the past, Rhodonite has also been used as an ornamental stone. It can be found in the former Soviet Union, the U.S., India, and Australia. The Mohs hardnessrating is 5.5 to 6.5.
Rhodochrosite (Greek: 'rose coloured') has only been on the market since the 1940's. It's a very pretty stone to look at; however it is very soft and very brittle. It has, in the past, been used for jewellery, ornaments and figurines. Transparent crystals are very rare and sought after by collectors. The most important deposits are in Argentina. Other significant deposits can be found in Peru, Germany, Mexico, South Africa, Russia, Italy, the USA, and Romania. Rhodochrosite has a Mohs hardnessrating of 3.5 to 4.
A ring is a piece of jewelry worn around the finger; rings can be worn on any finger, including the thumb. Rings have been worn throughout the ages, and often have significant meaning. Some rings include wedding and engagement rings (denoting commitment), rings denoting group membership (like Masonic rings or college rings), and devotional rings (with religious meaning). Rings come in just about any size you need (some larger rings will have to be specially made) and they can be made from many different alloys, plastics and stones.
This is one of the most common minerals of the earth's crust. The name crystal comes from the Greek for 'ice'. It was believed that Rock Crystal was eternally frozen. Rock Crystal weighting many, many kilograms has been found. However, cuttable material is rare. Important deposits have been found in Brazil, Madagascar, the USA, and the Alps. They are often used for costume jewellery and delicate ornaments to imitate Diamonds. It can be confused with many colourless gems as well as glass. Rock Crystal has a Mohs hardnessrating of 7.
Rose Quartz is named after its pink colour. It's a form of quartz that can have traces of rutile needles which can cause a Six-Rayed star (asterism) when cut into cabuchon. Deposits are found in Brazil and Madagascar as well as India, Namibia and Sri Lanka. Only larger stones can be faceted. Rose Quartz can be mistaken for Kunzite. Rose Quartz has a Mohs hardnessrating of 7.
Rubies are a very precious member of the Corundum family. The colour range is a deep red to purple/brown. The most sought after colour of the stone is what has been referred to as 'Pigeons Blood'. ItÆs a pure red colour with a hint of blue. As a rough stone, Ruby appears dull and greasy. However, when cut and polished, the lustre can come close to that of a Diamond. Just like Emeralds, occlusions in the stone can identify its authenticity. During the renaissance period Rubies were thought to have the power to counteract poison. The world's largest Ruby is known as the Raviratna it weights a whopping 3600 carats. Some of the most important deposits are in Burma, Thailand and Tanzania with only one percent of the rubies mined in these areas are of a gemstone quality. Rubies are a very hard gemstone with only Diamonds being superior. Rubies have a Mohs hardnessrating of 9.
Rutilated quartz is a type of rock crystal which contains long, fine needles of rutile crystals (titanium dioxide). This beautiful stone is usually cut as a cabochon. It is also known as Venus' Hair Stone, Cupid's darts, and Fleches d'amour (arrows of love). Rutilated Quartz has a Mohs hardnessrating of 7.
Sapphires are a very precious stone that has a wide range of colours from blue to white, green to purple. Sapphires are part of the Corundum family and in ancient times Sapphires were worn to protect the wearer from poisonous creatures. The Logan Sapphire is one of the largest faceted gemstones in the world weighting in at 422.99 carats (84.60g). The 3 most famous Sapphires: The Logan Sapphire, The Star Of India and The Star Of Bombay were all mined in Sri Lanka. The finest specimens of Sapphires are now mined in Kashmir. Sapphires have also been mined in Thailand, Australia and China. Sapphire has a Mohs hardnessrating of 9, second only to Diamonds.
A matt finish achieved by sandblasting, brushing with a stiff wire brush, or chemically altering a high shine surface. A Satin finish has a soft, Pearl-like luster instead of a bright polish.
Smokey Quartz is a member of the quartz family; it is brown in colour and has a smokey appearance. Smokey Quartz can sometimes have rutile needle occlusions. Deposits have been found Brazil, Madagascar, Russia, Scotland, Switzerland and the Ukraine. Smokey Quartz has a Mohs hardnessrating 7.
A snake chain (also called a Brazilian chain) is a metal chain made up of a series of small, linked cups. The body of the chain looks like that of a snake.
Sodalite is a mineral which can contain streaks of many colours some being white, grey or even green. In the past, it has been used for carvings and jewellery. Sodalite is one of the main mineral components that make up Lapis Lazuri. It has been mined in many countries such as Russia, the USA and Italy. The Mohs hardnessof the stone is 5.5- 6.
Spinel classifies a whole group of minerals, some of which are as follows: Flame Spinal, Balas Spinel, Pleoaste, and Picotite. Spinel is a very hard semi-precious stone that comes in a wide range of colours; red to black to yellow. It has been found in various countries around the world including Thailand, Sri Lanka and Burma. Spinal has a Mohs hardnessrating of 8.
Silver gets its symbol (Ag) from the Greek word Argyros. Silver is a fine, precious metal. Its colour is silver-white and it is often used in jewelry. Silver has to be alloyed (mixed) with other metals in order to use in jewellery production. This mixing of metals makes it more durable and rigid.
Jewellery and Silverware are traditionally made from Sterling Silver (standard silver), an alloy of 92.5% silver with 7.5% copper. Britannia silver is an alternative hallmarked-quality standard of the alloy containing 95.8% silver, often used to make silver tableware and wrought plate. Silver is often plated with Rhodiumfor a bright, shiny look which does not tarnish as quickly. However, under normal conditions with no plating, Silver will tarnish - it's the mixture of moisture and sulphur in the air we breathe that causes Silver to tarnish.
The largest piece of Silver ever found was in 1440 in Germany. Its dimensions were 2m x 4m with an approximate weight of 20 tonnes. It was named the "Silver Tableö due to its size and shape.
The main area of the world that Silver is mined today is Russia. The country produces around 15% of the world's total output, closely followed by Mexico. Canada, the USA, Peru, Bolivia and Germany have also have notable deposits.
A stud is a small earring usually decorated with either a small stone, an acrylic design, small shell, etc.
Sunstone is also called Aventurine. It was named after a type of glass that was discovered by chance and was called 'a ventura'. This gemstone varies in colour from golden to orange, from red to brown, and can sometimes contain a green or blue glitter effect caused by light reflections. The stone is usually cut flat or into a Cabochan. It can be found in several countries including India, the USA, Norway and Canada. Sunstone is very brittle with a Mohs hardnessrating of 6.
Tanzanite is a variety of the mineral zoisite. Tanzanite in its roughest form is a reddish, almost brown colour. It has to be treated at a very high temperature to produce that unique blue/purple colour it is famous for. The correct name for Tanzanite is 'Blue Zoisite', Tiffany's (The jewellers), however, thought this name wasn't appropriate, so it was named after the country where it was discovered in 1967, Tanzania. Tanzanite is a rare gem found mainly in the foot hills of Kilimanjaro. Tanzanite has a Mohs hardnessrating of 6.5 to 7.
Tiger's eye is member of the quartz group. This semi-precious stone is dark brown to yellow in colour with red colour being produced by applying heat to the stone. Tiger's Eye that is honey in colour is sometime passed off as the more expensive 'Cat's Eye'. Blue to grey coloured versions of the stone are called ôHawks Eyeö and the dark brown version of the stone is known as ôBull's eyeö or ôOx-eyeö. For jewellery, the stone is mostly cut into cabochans to bring out the streaks of colour that run right through the stone. The biggest percentage of Tiger's Eye comes from South Africa where the export of raw materials is forbidden. Other sources have been documented such as, Brazil, Burma, Canada, China and India. Tiger's Eye has a Mohs hardnessrating of 7.
A toggle clasp (also known as a T-BAR) is a fastener that can appear on either a bracelet or a necklace. It comprises of a ring on one end of the Bracelet/Necklace and a bar shaped like the letter ôTö on the other end which has to be wider that the ring to prevent it slipping out. The bar is passed through the ring which it then sits across to secure it in place.
Topaz in its purest form has no colour. It is usually coloured by the impurities from the surrounding land. Topaz can be found in many colours, some of which do not occur naturally. Take Mystic Topaz for example. This type of Topaz is created by applying an artificial coat to the stone which gives it that magical look. Blue Topaz in its natural form is very rare, so manufactures heat treat colourless topaz to create a deeper blue - more vibrant than a natural stone will ever posses. Topaz can be found in many countries around the Globe including Germany, Japan, Norway, the USA, Sri Lanka, Afghanistan and the Czech Republic. Topaz has a Mohs hardnessrating of 8.
Tourmaline is a gemstone with the widest colour range of any gemstone; the lighter colours being the most valuable. There are many variants of this stone which make it easier to break down the colour range. Rubelite can be rose red to pink in colour, Shorl is dark black in colour, Indicolite is light blue to a pale green, Verdelite is green and Achroite is colourless.
Gemstone quality Tourmaline is mainly mined in Brazil and Africa, but there are several other countries that have notable sources: Kenya, Nigeria, Namibia, Madagascar, Mozambique, Pakistan, Afghanistan, Sri Lanka, and Tanzania. Tourmaline has a Mohs hardnessrating of 7 to 7.5 .
A translucent material will allow light to pass through it, however it will scatter the light across the material/stone. Stones that are translucent include Carnelian, Moonstone and Opals. Certain types of plastic can be translucent.
Tsavorite is a rare member of the Garnet family. Its deep green colour is similar to that of Emerald, however it's a more durable stone and much rarer. Tsavorite stones that weigh over 2 carat are considered to be large and very rare. The gemstone was originally found in 1967 in Kenya. Tsavorite has a Mohs hardness rating of 7.5 .
The name Turquoise means 'Turkish Stone'. It gets this name from the route it took to get into Europe. Turquoise is a porous semi precious stone. It can have either a blue (pure blue stones are very rare) or green coloured surface with veins of black running right through it. Turquoise can be very soft and may be treated with a wax to help preserve the stone's life a little longer. The finest specimens of the stone come from deposits in Persia, Iran. Other well known deposits are in the USA, Israel, Afghanistan, Mexico and China. Turquoise has Mohs hardness rating of 6 to 7.
Vermeil is a French word that was introduced in to the English language in the 19th Century. Vermeil is a process where Sterling Silver is plated with Gold (at list 10K) and the layer has to be 1.5 micrometers thick to be considered true Vermeil.
White Gold is a gold alloy that is mixed with at least one white metal usually Nickel or Palladium. Like any other gold its purity is measured in Karats. Almost all white gold jewelry is Rhodium plated since gold alloyed with Palladium or nickel never comes out white, but tinted brown. It is therefore plated with Rhodium to mask the tinted shade and make it a true white colour.
Zircon is a mineral that can appear in many colours from colourless to red to brown to green. Colourless specimens that show gem quality are a popular substitute for diamonds. Zircon is not to be confused with Cubic Zirconia, which is a synthetic substance with a completely different chemical composition. Zircon is a very common mineral that occurs worldwide from Australia to Quebec. Australia leads the way in mining this mineral producing 37% of the worldÆs total output. Zircon has a Mohs hardness rating of 7.5.
Zoisite has three known forms: Anyolite, Tanzanite and Thulite. They are green, blue and pink in colour respectively. Zoisite was named after Slovenian mineral collector Baron Sigismund Zois von Edelstein, who financed the expedition that discovered Zoisite.
Zoisite can be sourced in the following locations. Tanzania (Tanzanite), Kenya (Anyolite), Norway (Thulite). Zoisite has a Mohs hardness rating of 6.5 .