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GARNET – Garnets are found in various shades and colours from brown to purple shades. But its dark red variety is valued as a precious stone although the mineral is quite common. Garnet crystals are 12 faced. The stones have been prized in jewellery for over 5000 years. When many garnet crystals are gathered in a rock cavity they are likened to a ripe pomegranate. Cut as brilliants, garnets are used as ring stones with large ones as pendants, often with cabochon cut and carved. Garnets and star garnets from are found in Australia.
JADE – This is the name given to both nephrite and jadeite which are tougher than steel although not particularly hard. China, New Zealand and Alaska supply good Jade. Burma also. Brazil it occurs naturally Used since Neolithic times for weapons and tools and later for delicate carvings. Aztecs used jade. In ancient Egypt the stone was called Nemehen. Pure Jade is white with impurities causing different colours and most pieces are mottled. It is generally translucent or opaque green in colour and is lustrous rather than brilliant. The most prised of all jades is “imperial jade” the transparent emerald green coloured by chromium. It has been always revered in China as a sacred stone. Its quality as a gemstone is judged by the intensity of the green colour and its coolness to the touch. Jadeite is the rarer of the jades and Myanmar remains the only commercial source. Much of the Central American jadeite originates in Guatemala. Soapy jade is the term for the inferior grades used commonly for carving decorations, lamp stands etc.
LAPIS LAZULI – This stone consists of blue silicate lazurite with variable amounts of calcite and the brassy gold flecks of pyrite which is more abundant in the poorer quality material. Afghanistan has the best quality that consists mostly of lazurite and is deep blue. In ancient times it was also known as “sapphirus”. The Egyptians used to ground it into pigment to use in paintings and murals and in eye shadow and used in manufacture of amulets and symbols, particularly in the representations of the goddess Isis and in the Sacred Eye of Horus. Later it was ground for use as pigment in religious paintings for the glorious blue of the Madonna’s robes. In China, royal seals and carvings were made of it. It is considered as a sacred stone in Buddhism. Lapis lazuli is one of the most ancient in items of jewellery – having been known and used for over 6000 years. It was mined in Afghanistan and Siberia near Lake Baikal, but nowadays produced profusely in Chile.
MOONSTONE – Moonstone is a Feldspar, comprised of calcium sodium or potassium aluminium silicates. Sri Lanka is the most important source of Moonstone. India produces strongly coloured stones as beige, pink, green, yellow, grey, white and brown. It is considered to be a sacred stone in India and by tradition, it is always cut en cabochon. It is an important stone in Ayurvedic medicine. Beautiful sheens come as with other stones, with subjected light and its particular sheen is called “adularescence” and most prized when the sheen is bluish in colour. Throughout the world it is associated with the Moon and very popular semi precious stone is used in jewellery everywhere. Their fascination lies in their gentle glowing and elusive sheen and above all the softness of their quality, compared with the strength and brilliance of faceted jewels.
OPAL – Opal is one of the few gem minerals which is non crystalline. Opals are referred to in history and in legend. Pliny is said to have liked it and Orpheus is said to have declared that the opal ‘fills the heart of the gods with joy”. Shakespeare refers to … “this miracle and Queen of gems”. Opal consists of pure silica (silicon combined with oxygen) with traces of numerous compounds which explains the many differing types. Opals were rare in antiquity. It is thought to have become commonly known only after the time of Alexander the Great. The only known mines in the earliest times were the Carpathian Mountains. The stone is extremely porous with the weight varying in proportion to the amount of contained water. The colours are determined by structure and the light which causes ever changing effect. Finest opal and opalized wood and fossils are found also in Australia at Coober Pedy and Andamooka. France also supplies some and also Idaho… Opals are usually cut as en cabochon. Their varieties include – Hungarian opals are very fine and were once popular in Europe.
Mexican Opals fine transparent variety of opal – Black opals are extremely vivid flashes of colour including red, with dark background and of highest value Milky opal or white opals are opaque with smaller and less spectacular softer markings and colours. Fire opals or Harlequin Opal is the finest quality and variety of gemstone Water Opal is clear and colourless with internal play of colour. Rose Opal or potch opal has a beautiful pink colour but opaque. Hydrophane Opal is opaque but appears colourless in water.
PEARL – Along with Coral, this extremely popular gemstone used in jewellery, is found in the seas not the land and is therefore not of the same composition nor characteristics of the earth born gemstones. Care must be taken to preserve the quality of pearls. Pearls are made of calcium carbonate formed within an oyster. The basic irritant is usually a grain of sand which stimulates the oyster to cover it with its own body secretion – eventually forming the well known round and perfect pearl. The lustre of the pearl comes from minute crackles on its surface – finer than those on opals. Their lustre increases in the body warmth of human beings and therefore the practice of allowing the shop attendants to wear the strings of pearl has a practical basis. Different pearl qualities depend upon colour and size and range from the tiniest “seed pearls” to the rare gems of considerable size Harvesting pearls from the wild is singularly unrewarding and cultured pearls have been able to meet the demand for these beautiful natural ornaments. Cultured pearls have been produced in China for several centuries as now in Japan, Australia and the Pacific.
RUBY – Next to diamond, rubies (and sapphires) are the most valued of the gems. Ruby is a variety of corundum, When the corundum includes chromium, it becomes ruby, when it contains titanium and iron instead and therefore is blue – the sapphire. The world’s finest come from Myanmar, Pakistan and Afghanistan, also Burma, Thailand, India and Ceylon .Burmese ones are exceptionally beautiful – found near Mogo N.E. of Mandalay. “Pigeon Blood” rubies are the highest in the scale of value. Thai Rubies are often found with spinel and are darker red than the Burmese Rubies. A fine ruby is a magnificent gemstone. Ruby has been synthetically produced successfully since 1904. But the genuine rubies are valued because of their rarity and therefore have not dropped in commercial value, in fact have risen. Rubies are also used in Space research in connection with communication systems to cut out surface sounds of the earth and pick up beams from space.
SAPPHIRE – Pink Sapphires, Blue sapphires and Yellow Sapphires are found in Thailand and East Africa. They are next to diamond in hardness and therefore resistant to wear. Australia is the largest producer of blue and golden sapphires. Non-blue sapphires are White Sapphires or Golden Sapphires. The largest sapphire known was 950 carats from Burma. The largest in Australia was 886 carats from Queensland in 1934. There are star sapphires and star rubies found which contain fine fibre crystals giving star effect when cut in en cabochon.
TOPAZ – Topaz is an aluminium silicate containing about 20% water and fluorine and comes in several colours. Yellow quartz is sold today under the name of topaz and it is one of the most popular colours, although there are others which are greenish and of reddish tint.. Golden Topaz from Brazil is a golden brown to pink colour. The main suppliers are Brazil, Germany and Russia. Japan also produces topaz. Topaz is harder than Rock crystal and is known for its huge crystals – a colourless one from Brazil was found weighing as much as 600 pounds, well formed and clear throughout. The largest known topaz was cut in 1977 and weighed 21,327 carats. Another is known at 36,853 carats. Found in Australia topaz is usually light yellow, green and blue also. Hardness 8 and Orthorhombic crystals brilliant and beautiful stone found in quartz rose rocks. Associated with tin ores . Tinted by heating. Sky blue topaz found in the Scottish Highlands, Brazil and Siberia.
TURQUOISE – This stone is composed of aluminium copper sulphate hydrated phosphate of aluminium and copper) and is only medium hard. Egyptians are the first people known to mine it in Sinai over 6000 years ago. The finest is said to be found in Naishapur, Iran, where it has been mined for about 3000 years. It is found also in Sinar, Turkestan and Tibet. The colours range from pale blue to deep green/blue. Water content affects the colour of the stone. It responds to human touch and warmth and in the Middle East is used as a reflector of babies’ health in the crib etc. It is relatively soft and has a waxy lustre. It is porous and its colour may deteriorate if skin oils and cosmetics are absorbed during wear. It’s famous for its change of colour when difficult influences are near and for this reason was attached to cradle of babies to reflect the child’s vitality and to alert them to any change in tone and colour. Some believe it becomes moist and changes colour when warning against Poison. The gem is regarded as a pledge of true affection and drawing evil influences. The green variety is found in New Mexico and in Australia.
