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All the colours of the rainbow!  What a wonderful sight.   Gems have intrigued us for at least 10,000 years.  The first used for making jewellery include Amethyst, Rock Crystal, Amber, Garnet, Jade, Jasper, Coral, Lapis Lazuli, Pearl, Emerald and Turquoise.   These stones were reserved for the wealthy and served as status symbols.  Rulers used to seal their documents with their jewel encrusted seals.   Such treasures can now be admired at many museums around the world.

Today gems are worn and bought increasingly for pleasure in appreciation of their outstanding colour and beauty.

There are several hundred distinct types of gems and gem materials.  Harder stones are suitable for jewellery.

Some of the most popular semi precious gemstones that are used in my jewellery are:-

Agate, Amethyst, Aquamarine, Aventurine, Beryl, Carnelian, Chalcedony, Charoite, Citrine, Coral, Emerald, Fluorite, Garnet, Green Lace Stone, Howlite, Iolite, Jade, Jasper, Kunzite, Kyanite, Labradorite, Lapis Lazuli, Malachite, Moonstone, Mother of Pearl, Nephrite, New Mountain Jade, Olivine, Onyx, Opal, Pearl, Peridot, Rock Crystal, Rose Quartz, Ruby, Sapphire, Shell, Smokey Quartz, Tigers Eye, Topaz, Tourmaline and Turquoise


AMETHYST - Passionate for Purple!!

The wondrous Amethyst, noble coloured gemstone that cannot fail to impress - admired by so many women around the world.    Amethyst was first used by the ancient Egyptians - the Greeks also believing it to be a cure for drunkenness - the word Amethyst is derived from the Greek word - "amethystos" - which means "not drunk"  and the Greeks wore it as an amulet to ward off drunkenness - doubtful though that it will now keep you girls sober on your nights out!!!!!

The majority of Amethyst is now found in Brazil, Zambia, Sri Lanka, India, Canada and Mexico. 


Agate is a banded concentric shell like chalcedony, sometimes containing opal substance.  The fine quartz fibres are oriented vertically to the surface of the individual band layers.   The bands can be multicoloured or of the same colour.   The most important deposits today are found in the south of Brazil and in the north of Uruguay.   Other deposits are found in Australia, China, India, the Caucasus, Madagascar, Mexico, Mongolia, Namibia and in the USA (Wyoming and Montana).  The most important Agate deposits were found at the beginning of the 19th century in the neighbourhood of Idar-Oberstein/Rhineland, Germany.   These deposits have all now been mined.


Aquamarine which is Latin and means "water of the sea" is so named because of its beautiful turquoise sea water colour.  A dark blue is the most desired colour.   The most important deposits are in Brazil, spread throughout the country.  The well known deposits in Russia (the Urals) seem to have been worked out.  Other deposits are in Australia, Burma, China, India, Kenya, Madagascar, Mozambique, Namibia, Nigeria, Zambia, Zimbabwe and the USA.

The largest Aquamarine of gemstone quality was found in 1910 in Marambaya, Minas Gerais, Brazil.  It weighed 243lb (110.5kg), was 18 inches (48.5cms) long and 15.5 inches (42cms) in diameter and was cut into many stones with a total weight of over 100,000 carats.


Aventurine is a type of glass discovered by chance (Italian - a ventura) around 1700 gave the same name to the similar looking stone.  Mostly dark green with metallic glittery appearance caused by included fuchsite (green mica) or red to gold brown caused by hematite leaves.  Deposits are found in Brazil, India, Austria (Steiermark), Russia (Urals, Siberia) and Tanzania.


Carnelian is probably named after the colour of the kornel cherry because of its colour.  It is a brownish red to orange, translucent to opaque chalcedony variety.   The colouring agent is iron.   Deposits are found in Brazil, India and Uruguay.   The stone was used extensively by the Romans as they used it for sealing their wax seals on their important  documentation as the wax did not stick to Carnelian stone.


Citrine the name is derived from its lemon yellow colour.  The colouring agent is iron.  Natural citrines are rare.  Most commercial citrines are heat treated amethysts or smokey quartzes.  Brazilian amethyst turns light yellow at 878 degrees F (470 degrees C) and dark yellow to red brown at 1022-1040 degrees F (550-56- degrees C).  Some smokey quartzes turn into citrine colour already at about 390 degrees F (200 degrees C).  Natural citrines are mostly pale yellow.  Deposits of natural coloured citrines are found in Brazil, Madagascar and the USA, as well as in Argentina, Burma, Namibia, Russia, Scotland and Spain.


Coral a name of Greek origin used as gem material is a branching skeleton like structure built by small marine animals (coral polyps) related to reef-forming corals.  The height of the branches is in the general range of 8 to 10 inches (20-40cms) and the branches are up to 2.5 inches (6cms) thick.   Deposits are found along the coasts of the western Mediterranean countries, the Red Sea, Bay of Biscay, Canary Islands, Malaysian Archipelago, the Midway Islands, Japan, and Hawaii (USA).  Production is increasingly controlled by environmental laws.

The coral is found at depths of 1-1020 feet (3-300 metres) and mainly harvested with weighted wide meshed nets dredged across the seabed.  When harvested by divers, however, not as many corals are damaged.  Near Hawaii, minisubmarines have recently been used to collect the coral.  When it is brought to the surface, the soft parts are rubbed away and the material is sorted as to quality.  For more than 200 years the main trade center has been Torre Del Greco, south of Naples, Italy.  Three quarters of the coral harvested all over the world is still processed there.

Unworked coral is dull when polished it has a vitreous luster.  It is polished with fine grained sandstone and emery and then finely polished with felt wheels.   Noble Coral is the most desired of all coral types.   The colour is uniform; light red to salmon coloured, medium red, ox-blood red, tender pink with whitish or light-reddish spots (known as Angel Skin coral).  Coral is sensitive to heat, acids and hot solutions.   Take care when wearing this beautiful organic gemstone!


The name Emerald derives from the Green word "smaragdos" which means "green stone" and in ancient times referred not only to emeralds but also probably to most green stones.    Emerald is the most precious stone in the beryl group.  Its green is incomparable and is therefore called "emerald green".  The colouring agent for the "real emerald" is chrome.  Beryls that are coloured by vanadium ought to be called "green beryl" and not emerald.  The colour is very stable against light and heat, and only alters at 1292-1472 degrees F (700-800 degrees C).  The colour distribution is often irregular a dark slightly bluish green is the most desired.

Only the finest specimens are transparent.  Often the emerald is clouded by inclusions.  These are not necessarily classified as faults, but are evidence as to the genuineness of the stone as compared with synthetic and other imitations.  The expert refers to these inclusions as jardin (French for garden).

Significant deposits are found in Colombia, especially the Muzo mine northwest of Bogota.  First mined by native tribes the Muzo deposit was abandoned and rediscovered in the 17th century.  The mine yields fine quality stones of a deep green colour.   Mining, apart from shafts, is mainly by step form terraces.  The emerald bearing soft broken rock is loosened with sticks, lately also through blasting or with bulldozers and the emeralds picked out by hand.  The host rock is a dark carbonaceous limestone.   Accompanying minerals are albite, apatite, aragonite, barite, calcite, dolomite, fluorite and pyrite.

Emerald deposits were first discovered in 1830 in Russia.   Further emerald deposits are now found in Afghanistan, Australia, Ghana, India, Madagascar, Malawi, Mozambique, Namibia, Nigeria, Pakistan, Zambia, Tanzania and in North Carolina (USA).  The emerald mines of Cleopatra (perhaps worked as early as 2000BC east of Aswan in upper Egypt are now of historical use only.


The colour of Iolite (Greek word for Violet) is usually blue.  Inclusions of hematite and goethite sometimes cause a reddish sheen or aventurescence.   Deposits are found in Myanmar, Brazil, India, Sri Lanka and the USA.  It is sometimes confused with sapphire and tanzanite.


The name Jade goes back to the time of the Spanish conquest of Central and South America and derives from 'piedra de ijada'  -  ie.,  hip stones, as it was seen as a protection against and cure for kidney diseases.  The corresponding Chinese word  'yu'  has not been generally accepted.    In 1863 in France, the gemstone which had been known for 7,000 years, was proved to consist of two separate distinct minerals namely jadeite and nephrite.  Differentiation between jadeite and nephrite is based on properties but the term jade is used as a description of both.   In prehistroic times jade was used in many parts of the world for arms and tools because of its exceptional toughness.  Therefore nephrite is sometimes called "axe stone".   For over 2,000 years jade was part of the religious cult in China and mystic figures and other symbols were carved for it.   In pre-Columbian Central America, jade was more highly valued than gold.   With the Spanish conquest, the high art of jade carving in America came to a sudden end.   In China, however, this art was never interrupted.   In former times only nephrite was worked in China, but since about 1750 jadeite imported from Myanmar has also been used.


This is the violet pink transparent variety of spodumene, it is named after the American mineralogist G F Kunz who was a noted gem expert active at the turn of the century.  The characteristic colour is a violet pink which can be quite intense.  Kunzite is found in the USA (in various parts of California, Maine and Connecticut), Brazil and Madagascar.


The name Labradorite is derived from its main source Labrador in Canada.  It has a wonderful blue iridescence on a dark ground.  The ground colour is a dark smoke grey but when light strikes it in a particular direction it displays striking rainbow coloured reflections (violet, blue, green, yellow and even orange and reddish) known as labradorescence.  The labradorite used in gems comes mainly from Canada and Finland.


The name of the gem is derived through the medieval Latin lapis lazulus, from the Arabic word lazward, from which the word Azure comes.  Scientifically speaking lapis lazuli is a 'rock' because it consists of an association of minerals, lazurite and variable quantities of calcite and pyrite.  The best quality lapis lazuli comes from Afghanistan where it has been mined since remote antiquity.  The ancient Egyptians probably obtained their supplies from there.  It is also found in Chile but usually with numerous light patches and veins.   It is one of the most valuable semi opaque ornamental materials, worth about the same as good quality turquoise and the better jades.


The name is derived from the Greek 'malakhe' meaning 'mallow' evidently because of the colour.   The colour is always green which can be described as mallow green to a very dark even blackish green.  These tones appear as a rule in alternate stripes.  In the past most malachite came from the Soviet Union but nowadays large quantities are also obtained from Zaire, Zimbabwe, Namibia, Chile, the USA and Australia.


The stone is known as nephrite because in early times it was used in amulets against kidney disorders.  Both jadeite and nephrite are known as jade.  Nephrite can be dark green to blackish, grey or blue grey.  Greyish white is also very common.   Because of its exceptional toughness it is used for the carving of figurines, it is also made into necklaces, beads and pendants.


The name is derived from an Indian (Sanskrit) word for 'stone'.  It is divided into three subgroups - the precious opals, the yellow-red fire opals, and the common opals.   The special characteristic of these gems is their play of colour a display of rainbow like hues which changes with the angle of observation.   Up to the end of the 19th Century the andesite lavas in the east of Slovaki supplied the best qualities.  Australian deposits were then found, other deposits are found in Brazil, Guatemala, Honduras, Indonesia, Japan, Mexico, Russia, Nevada and Idaho.


Most pearls are products of bivalve mollusks mainly of the oyster type.  They are built up of mother of pearl (nacre) which is mainly calcium carbonate and an organic horn substance that binds the microcrystals around an irritant.  They are extremely strong and it is very difficult to crush them.  The size of pearls varies between a pin head and a pigeons egg.  One of the largest fine pearls ever found (called the Hope Pearl after a former owner) is 2ins (5cms) long and weights 454ct (90.8 grams), it is in the South Kensington Museum London.  The colour of the pearl varies with the type of mullusk and the water and is dependent on the colour of the upper conchiolin layer.  All pearls are formed as a result of an irritant that has intruded between the shell of the mollusk and the mantle.  Natural pearls come into being without intervention by human beings in the ocean as well as in freshwater.  Since the 1950's cultured pearls were from Japan but they are now cultivated in China but their quality is not as good as Japanese pearls.   Mother of Pearl is the inner nacreous layer of the mollusk shell which has a beautiful play of colour to it. 


Quartz is named after a Slavic word for 'hard' and is the name for a group of minerals of the same chemical composition and similar physical properties. Macrocrystalline Quartz (crystals that are recognisable with the naked eye) includes stones gemologists classify as varieties of the quartz species; amethyst, aventurine, rock crystal, blue quartz, citrine, hawk's eye, praiolite, quartz cat's eye, smokey quartz, rose quartz and tiger's eye.  Cryptocrystalline Quartz (microscopically small crystals) generally known as chalcedony, includes agate, petrified wood, chrystoprase, bloodstone, jasper, carnelian, moss agate and sard.


Ruby is thus named because of its red colour (Latin name - Ruber).  It was not until about 1800 that ruby as well as sapphire was recognised as belonging to the corundum species.  Before that red spinel and the red garnet were also designated as ruby.  The red colour varies within each individual deposit, so it is not possible to determine the source area from the colour.  The most desirable colour is the so called 'pigeons blood' pure red with a hint of blue.  The distribution of colour is often uneven in stripes or spots.  The substance that provides the colour is chromium and in the case of brownish tones iron is present as well.  Ruby is the hardest mineral after diamond.  Some of the most popular deposits are in Myanmar, Thailand, Sri Lanka and Tanzania.  Rubies from Thailand often have a brown or violet tint to them.  They are found southeast of Bangkok in the district of Chantaburi in clayey gravels.  The largest cuttable ruby weighed 400carats it was found in Burma and divided into three parts.  


The name Sapphire (Greek - blue) used to be applied to various stones.  At first only the blue variety was called sapphire, today corundums of gemstone quality of all colours except red are called sapphire. Through heat treatment at temperatures of about 3100 degrees F some cloudy sapphires nondistinct in colour can change to a bright blue permanent colour.  Important sapphire deposits are found in Australia, Myanmar, Sri Lanka and Thailand.  The American Museum of Natural History (New York) owns the "Star of India" perhaps the largest cut star sapphire (536 carats).


The name Topaz is most probably derived from an island in the Red Sea now Zabargad but formerly Topazos the ancient source of peridot.   The most common colour is yellow with a red tint the most valuable is pink to reddish orange.  The colouring agents are iron and chromium.   The colours found can be colourless, yellow, orange, red-brown, light to dark blue, pink-red, violet and light green.   Today Brazil is the most important supplier other deposits are found in Afghanistan, Australia, Burma, China, Japan, Madagascar, Mexico.   Light blue topazes are found also in Northern Ireland, Scotland and Cornwall.


The name turquoise means 'Turkish Stone' because the trade route that brought it to Europe used to come via Turkey.  Pure blue colour is rare mostly turquoise is interspersed with brown, dark grey or black veins of other minerals or the host rock.  Such stones are called turquoise matrix.  The popular sky blue colour changes at 482 degrees F into a dull green.  A negative change in colour can also be brought about by the influence of light perspiration, oils, cosmetics and household detergents.  Turquoise rings should be removed before hands are washed.  The best quality of Turquoise is found in Iran, additional deposits are found in Afghanistan, Argentina, Australia, Brazil, China, Israel, Mexico, Tanzania and the USA.   The deposits in Sinai Egypt were already worked out by 2000B.C.  In the early Victorian period sky blue turquoise was most popular.  Today it is used en cabochon for brooches, necklaces and bracelets as well as ornamental objects.

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