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Aventurine

A form of quartz that has a green jade-like colour which is unusual because it incorporates particles of Mica or sometimes Haematite. These give it a glittering appearance that changes as you rotate it. The main deposits of Adventurine are found in the mountains of Russia.

Agate

Agate is a microcrystalline variety of quartz, characterised by its fineness of grain and brightness of colour. Although agates may be found in various kinds of rock, they are normally associated with volcanic rocks but can be common in certain metamorphic rocks.

Colourful agates and other chalcedonies were obtained over 3,000 years ago from the Achates River, now called Dirillo, in Sicily.

The stone was given its name by Theophrastus, a Greek philosopher and naturalist, who discovered the stone along the shore line of the river Achates sometime between the 4th and 3rd centuries BC. Agate has been recovered at a number of ancient sites, indicating its widespread use in the ancient world; for example, archaeological recovery at the Knossos site on Crete illustrates its role in Bronze Age Minoan culture.

Amber

Amber is fossil tree resin, which is appreciated for its colour and beauty. Good quality amber is used for the manufacture of ornamental objects and jewellery. Although not mineralized, it is often classified as a gemstone.

A common misconception is that amber is made of tree sap; it is not. Sap is the fluid that circulates through a plant's vascular system, while resin is the semi-solid amorphous organic substance secreted in pockets and canals through epithelial cells of the plant.

Because it used to be soft and sticky tree resin, amber can sometimes contain insects and even small vertebrates.

Amber occurs in a range of different colours. As well as the usual yellow-orange-brown that is associated with the colour "amber", amber itself can range from a whitish colour through a pale lemon yellow, to brown and almost black. Other more uncommon colours include red amber (sometimes known as "cherry amber"), green amber, and even blue amber, which is rare and highly sought after.

Amethyst

Amethyst is a violet variety of quartz often used as an ornamental stone in jewellery. The name comes from the Ancient Greek a- ("not") and methustos ("intoxicated"), a reference to the belief that the stone protected its owner from drunkenness; the ancient Greeks and Romans wore amethyst and made drinking vessels of it in the belief that it would prevent intoxication.

Cats Eye

Cats Eye gemstone possesses a unique effect that resembles the eye of a cat. This effect in cats eye is caused by the reflection of light within tiny parallel fibres. This is technically called chatoyancy. True cat's eye jewellery is created with a variety of chrysoberyl, the third hardest of all minerals. This is also the same mineral from which alexandrite comes. Cats eye jewellery is often made using cabochon cut specimens in order to accentuate its unique characteristic.

Citrine

Citrine occurs naturally in proximity to Amethyst and is a related Quartz. The colour of Citrine is due to small amounts of iron in the crystal structure of Quartz.

Citrine ranges in colour from lemon yellow to golden yellow to mandarin orange and red. Most of the Citrine mined today comes from Uruguay, Brazil and many African nations including Madagascar. Citrine can be easily confused with Topaz and has even been called Topaz Quartz.

Coral

Corals are marine organisms from the class Anthozoa and exist as small sea anemone like polyps, typically in colonies of many identical individuals. The group includes the important reef builders that are found in tropical oceans, which secrete calcium carbonate to form a hard skeleton.

Coral has been used as a gemstone since pre-historic times. It has been incorporated into beaded jewellery and worn as an amulet to ward off the evil and has had a long historical association with religious meaning.
Most coral today is harvested in and around the Mediterranean sea or in the Pacific Ocean near Japan and Taiwan and is usually a white thin twig like coral that is dyed red. Sponge coral is also used and can be dyed into many different colours.

Although natural coral can be black or brown as found in Hawaii, as well as light-dark Orange most people think of coral as red or light orange in colour.

Dichroic Glass

Multiple ultra-thin layers of different metal oxides (gold, silver, titanium, chromium, aluminium, zirconium, magnesium, silicon) are vaporised by an electron beam in a vacuum chamber. The vapour then condenses on the surface of the glass in the form of a crystal structure. This is sometimes followed by a protective layer of quartz crystal. The finished glass can have as many as 30 to 50 layers of these materials yet the thickness of the total coating is approximately 30 to 35 millionths of an inch (about 760 to 890 nm). The coating that is created is very similar to a gemstone and, by careful control of thickness, different colours are obtained.

Enamel

Enamelling is the fusion of a special powdered glass to metals. The glass can be applied using different techniques, but all methods use heat to melt the powder.

Garnet

The garnet group includes a group of minerals that have been used since the Bronze Age as gemstones and abrasives. The name "garnet" comes from the Latin granatus ("grain"), possibly a reference to the Punica granatum ("pomegranate"), a plant with red seeds similar in shape, size, and colour to some garnet crystals.

Goldstone

Goldstone is a type of glittering glass made in the presence of a reducing flame. The finished product can take a smooth polish and be carved into beads, figurines, or other artefacts suitable for semiprecious stone, and in fact goldstone is often mistaken or misrepresented as a natural material.

The most common form of goldstone appears to be reddish-brown, due to the presence of tiny crystals of metallic copper. When the reduced goldstone melt cools, the copper remains in atomic isolation and precipitates into small crystalline clusters which reflect light through the surrounding transparent or translucent glass, rendering the final product effectively opaque. (Under normal oxidative conditions, copper ions meld into the silica to produce transparent bluish-green glass.) Some goldstone variants have an intensely-coloured glass matrix??- usually blue or violet, more rarely green??- and a more silvery appearance to the suspended crystals, whose colour may be partially masked by the glass, or which may be based on different metals (perhaps cobalt, manganese, or chromium).

Jasper

Jasper is an opaque impure variety of silica usually red, yellow or brown in colour. This mineral breaks with a smooth surface and is used for ornamentation or as a gemstone. It can be highly polished and is used for vases, seals, and at one time for snuff boxes. When the colours are in stripes or bands, it is called striped or banded jasper. Jaspilite is a banded iron formation rock that often has distinctive bands of jasper. Jasper is basically chert which owes its red colour to iron inclusions.

Jet

Jet is a product of high pressure decomposition of wood from millions of years ago, commonly the wood of trees of the Araucariaceae family. Jet is found in two forms, hard and soft. Hard jet is the result of the carbon compression and salt water; soft jet is the result of the carbon compression and fresh water. Jet is easily polished and is used in manufacturing jewellery, according to the Whitby Museum, dating from 10,000 BC in parts of contemporary Germany. The oldest jet jewellery was found in Asturias, Spain, dating from 17,000 BC.

Labradorite

Labradorite is a feldspar mineral, an intermediate to calcic member of the plagioclase series. The streak is white, like most silicates. As with all plagioclase members the crystal system is triclinic and three directions of cleavage are present two of which form nearly right angle prisms. It occurs as clear, white to gray, blocky to lath shaped grains in common mafic igneous rocks such as basalt and gabbro, as well as in anorthosites.

The geological type area for Labradorite is Paul's Island near the town of Nain in Labrador, Canada. It occurs in large crystal masses in anorthosite and shows an iridescence or play of colours. The iridescence is the result of light refracting within lamellar intergrowths resulting from phase exsolution on cooling in the Boggild miscibility gap.

Gemstone varieties of Labradorite exhibiting a high degree of iridescence are called spectrolite; moonstone and sunstone are also commonly used terms, and high-quality samples with good iridescent qualities are desired for jewellery.

Lapis

Lapis lazuli is a rock, not a mineral: whereas a mineral has only one constituent, lapis lazuli is formed from more than one mineral.

The main component of lapis lazuli is lazurite (25% to 40%), a feldspathoid silicate mineral composed of sodium, aluminium, silicon, oxygen, sulphur, and chloride. Most lapis lazuli also contains calcite (white), sodalite (blue) and pyrite (metallic yellow). Other possible constituents are augite, diopside, enstatite, mica, hauynite, hornblende and nosean. Some contain trace amounts of the sulphur rich lollingite variety geyerite.

Lapis lazuli usually occurs in crystalline marble as a result of contact metamorphism.

The finest colour is intense blue, lightly dusted with small flecks of golden pyrite. Stones with no white calcite veins and only small pyrite inclusions are more prized. Patches of pyrite are an important help in identifying the stone as genuine and do not detract from its value. Often, inferior lapis is dyed to improve its colour, producing a very dark blue with a noticeable grey cast which may also appear as a milky shade.

Malachite

Malachite often results from weathering of copper ores and is often found together with azurite, goethite, and calcite. Except for its vibrant green colour, the properties of malachite are similar to those of azurite and aggregates of the two minerals occur frequently together. Malachite is more common than azurite and is typically associated with copper deposits around limestone, the source of the carbonate.

Large quantities of malachite have been mined in the Urals. It is found in the Democratic Republic of Congo; Zambia; Tsumeb, Namibia; Ural mountains, Russia; Mexico; Broken Hill, New South Wales; England; Lyon; and in the South-western United States especially in Arkansas and Arizona. In Israel, malachite is extensively mined at Timna valley, often called King Solomon's Mines although research has shown that the site was not in use during the 10th century. Archaeological evidence indicates that the mineral has been mined and smelted at the site for over 3,000 years. Most of Timna's current production is also smelted, but the finest pieces are worked into silver jewellery.

Moonstone

The moonstone is characterised by an enchanting play of light. Indeed it owes its name to that mysterious shimmer which always looks different when the stone is moved and is known in the trade as 'adularescence'. In earlier times, people believed they could recognise in it the crescent and waning phases of the moon.

Moonstones from Sri Lanka, the classical country of origin of the moonstone, shimmer in pale blue on an almost transparent background. Specimens from India feature a nebulous interplay of light and shadow on a background of beige-brown, green, orange or brown. These discreet colours, in connection with the fine shimmer, make the moonstone an ideal gemstone for jewellery. This gemstone was very popular once before, about a hundred years ago at the time of Art Nouveau. It adorns a noticeably large number of the jewellery creations of the French master goldsmith Ren?? Lalique and his contemporaries, mainly to be found in museums and collections today.

Mother of Pearl

Nacre, also known as mother of pearl, is an organic-inorganic composite material produced by some molluscs as an inner shell layer. It is strong, resilient, and iridescent. For more information on shell structure see: Mollusc shell.

This substance is called "mother of pearl" because it is literally the "mother", or creator, of true pearls.

Nacre is found in certain ancient lineages of bivalves, gastropods and cephalopods. However, the inner-shell layer in the great majority of shelled molluscs is porcellaneous and non-nacreous, frequently resulting in a non-iridescent shine like that of a porcelain plate or, in some species, presenting non-nacreous iridescent effects such as 'flame structure' (e.g. conch pearl).

Pearls and the inside layer of pearl oyster shells and freshwater pearl mussel shells are made of nacre. Many other families of molluscs also have an inner shell layer which is nacreous, including marine gastropods such as the Haliotidae, the Trochidae and the Turbinidae.

Onyx

Onyx is a cryptocrystalline form of quartz. The colours of its bands range from white to almost every colour (save some shades, such as purple or blue). Commonly, specimens of onyx available contain bands of colours of white, tan, and brown. Sardonyx is a variant in which the coloured bands are sard (shades of red) rather than black. Pure black onyx is common, and perhaps the most famous variety, but not as common as onyx with banded colours.

Paua Shell

It is unique to New Zealand - it is the most colourful shell in the world - it is a species of Abalone(Haliotis Iris).
Paua are primarily caught for their meat, which is a traditional delicacy of the Maori. There is a strict quota system in place to sustain the management of paua fishery.

The real paua shell material is unique and should not be compared to the cheap blue resin coated paua jewellery that has flooded the market. Our pieces of jewellery only use the real material, taken from thick paua shells and not treated in any way to artificially enhance colours.

All designs use the paua shell as is and explore the magic of this shell. Each shell is different in colour, making every piece of jewellery truly unique. The colours change when viewed from different angles, and it is this iridescence that make paua shell and the jewellery created with it magical!

Peridot

Peridot is one of the few gemstones that occur in only one colour: basically an olive green. The intensity and tint of the green however depends on how much iron is contained in the crystal structure, so the colour of individual peridot gems can vary from yellow-green through olive green to brownish green. The most valuable is considered a dark-olive green colour.

Peridot crystals have been collected from some Pallasite meteorites. A famous Pallasite was offered for auction in April 2008 with a requested price of close to $ 3 million at Bonhams, but remained unsold. Peridot is the only gemstone found in meteorites.

Peridot olivine is the birthstone for August. It is sometimes mistaken for emeralds and other green gems. In fact notable gemmologist George Frederick Kunz discussed the confusion between Emeralds and Peridots in many church treasures, notably the "Three Magi" treasure in the Dom of Cologne, Germany.

Pyrites

The mineral pyrite, or iron pyrite, is an iron sulphide with the formula FeS2. This mineral's metallic lustre and pale-to-normal, brass-yellow hue have earned it the nickname fool's gold due to its resemblance to gold. Pyrite is the most common of the sulphide minerals. This name is likely due to the sparks that result when pyrite is struck against steel or flint.

Pyrite is usually found associated with other sulphides or oxides in quartz veins, sedimentary rock, and metamorphic rock, as well as in coal beds, and as a replacement mineral in fossils. Despite being nicknamed fool's gold, small quantities of gold are sometimes found associated with pyrite. Gold and arsenic occur as a coupled substitution in the pyrite structure. In the Carlin, Nevada gold deposit, arsenian pyrite contains up to 0.37 wt% gold. Auriferous pyrite is a valuable ore of gold.

Rose Quartz

Pure quartz is colourless or white; common coloured varieties include rose quartz, amethyst, smoky quartz, milky quartz, and others. Quartz goes by an array of different names. The most important distinction between types of quartz is that of macro crystalline (individual crystals visible to the unaided eye) and the microcrystalline or cryptocrystalline varieties (aggregates of crystals visible only under high magnification). The cryptocrystalline varieties are either translucent or mostly opaque, while the transparent varieties tend to be macro crystalline. Chalcedony is a cryptocrystalline form of silica consisting of fine intergrowths of both quartz, and its monoclinic polymorph moganite.

Tiger Shell

The handsome shell of this fish is recognised by its delicately tapered spire and conspicuous pattern of zigzag reddish-brown stripes. It lives under boulders and ledges in clean water-sheltered situations, but is not common. It grows to 3 in. in diameter. Whangarei Heads, Manukau Heads, Mount Maunganui, and Whanganui Inlet are good localities for this beautiful species.

Tigers Eye

Tiger's eye (also Tigers eye, Tiger eye) is a chatoyant gemstone that is usually a metamorphic rock that is yellow- to red-brown, with a silky lustre. A member of the quartz group, it is a classic example of pseudomorphous replacement by silica of fibrous crocidolite (blue asbestos). An incompletely silicified blue variant is called Hawk's eye.

The gems are usually cut en cabochon in order to best display their chatoyancy. Red stones are brought about through gentle heat treatment. Honey-coloured stones have been used to imitate the much higher valued cat's eye chrysoberyl (cymophane), but the overall effect is unconvincing. Artificial fiberoptic glass is a common imitation of tiger's eye, and is produced in a wide range of colours. Tiger's Eye mostly comes from South Africa.

Topaz

Pure topaz is colourless and transparent but is usually tinted by impurities; typical topaz is wine- or straw yellow, pale gray, or pink. They may be made white, gray, pale green, blue, pink or reddish-yellow and transparent or translucent.

Yellow topaz is the traditional November birthstone, the symbol of friendship, and the state gemstone for the US State of Utah.

Blue topaz is the December birthstone and Texas state gemstone. Topaz very rarely occurs blue naturally. Typically, colourless, gray or pale yellow material is heat treated and irradiated in order to turn it blue.

Mystic topaz is colourless topaz which has artificially treated with a thin film/coating giving it the desired rainbow effect, and is not a naturally occurring topaz.

Turquoise

Turquoise is an opaque, blue-to-green mineral that is a hydrous phosphate of copper and aluminium. It is rare and valuable in finer grades and has been prized as a gem and ornamental stone for thousands of years owing to its unique hue. In recent times turquoise, like most other opaque gems, has been devalued by the introduction of treatments, imitations, and synthetics onto the market, some difficult to detect even by experts.

The substance has been known by many names, but the word turquoise was derived around 16th century from the French language either from the word for Turkish (Turquois) or dark-blue stone (pierre turquin). This may have arisen from a misconception: turquoise does not occur in Turkey but was traded at Turkish bazaars to Venetian merchants who brought it to Europe. The colour, however, has been employed extensively in the decorative tiles adorning Turkish places of worship and homes for hundreds of years, beginning with the Seljuks, or was derived from the colour of the Mediterranean Sea on the southern Turkish coast and the association quite possibly has caused the name to take root.