Guide to Gemstones

guide to gemstones

Gemstones have played various roles in the myths and legends of human cultures throughout history. Some tell a story or are believed to have special powers, but all of them share a common beauty.

guide to gemstones

Gemstones have played various roles in the myths and legends of human cultures throughout history. Some tell a story or are believed to have special powers, but all of them share a common beauty. Each gemstone is unique with a special colour, birthplace and story. Some of the most popular gemstones found in jewellery today are described below.


Amethyst

Amethyst is a transparent purple quartz. Its name comes from the Greek “amethystos”, which means “not drunken”, because amethyst was considered to be a strong antidote against drunkenness in Greek legend.
The colour range varies from pale lilac to deep purple.


Aquamarine

Aquamarine belongs to the gemstone family of beryls. The origin of the name is the Latin “aqua”, meaning water and “mar”, sea. Legend has it that mermaids’ tails were made of aquamarine.
Aquamarine is usually free of inclusions and possesses a superior brilliance. The more intense the colour of an aquamarine, the higher its value. Colour is pale blue to light greenish.


Citrine

Citrine is a form of quartz with ferric iron impurities and is rarely found naturally. Its name comes the French word “citron”, meaning lemon. Most commercial citrine is actually heat-treated amethyst or smoky quartz.
The different shades range from yellow, gold, orange brown shades of transparent quartz.


Cubic Zirconia

Cubic zirconia, or CZ, is a synthetic variant of the mineral baddeleyite, which is extremely rare in nature. It was first used in the Russian space programme to serve as a window to photograph through, and was not used in jewellery until 1969 when the material was first faceted.
By adding other minerals in the creative process, CZs can come in any colour as well as the colourless variety.


Diamond

The word “diamond” comes from the Greek for invincible, and diamonds are the hardest natural substance known to man. Natural diamonds are pure carbon, formed into crystals deep below the earth's crust millions of years ago.
Diamonds come in all colours. The colour of a fancy coloured diamond is measured differently to a white diamond. One out of 10,000 normal diamonds is a fancy colour diamond.


Emerald

Emerald is a valuable beryl that owes its colour to chromium or vanadium, which makes it bright green. “Emerald” is said to be a Sanskrit word meaning green. Emeralds can have many inclusions and flaws so can be brittle and liable to break.
Emeralds come in many shades of green and bluish green. Many emeralds are treated to hide surface-reaching breaks and improve transparency.


Opal

Opal is a type of quartz and its name comes from the Sanskrit word “upala”, meaning precious stone. They are luminous and iridescent with inclusions of many colours. Almost 95% of all fine opals come from the dry and remote outback deserts of Australia.
Opals are very infrequently of a singular colour and are most commonly white, black, red, and orange, most of the full spectrum, colourless, and iridescent.


Pearl

A pearl is a smooth, lustrous, chiefly calcium carbonate organic gemstone. Natural pearls are nearly 100% nacre, a protective mother of pearl coating that is secreted to protect the organism for a foreign body that has entered the shell. Natural or real pearls come mainly from oysters, although there are other bi-valve molluscs that can produce them.
Cultured pearls are produced by artificially introducing a foreign object into the fleshy part of oysters, which become coated with nacre in a similar manner to natural pearls.
Pearls tend to be white or cream, but the colour can vary according to the natural colour of the nacre in the various species of mollusc used. They can also be black or various pastel shades. Pearls (especially freshwater pearls) can be dyed yellow, green, blue, brown, pink, purple, or black.


Peridot

Peridot is the gem quality variety of the mineral olivine. Its name either comes from the Arabic word “faridat”, meaning “gem,” or the French word “peritot”, meaning “unclear”.
Peridot is one of the few gemstones that comes in only one colour. The depth of green depends on how much iron is contained in the crystal structure and varies from yellow-green to olive to brownish green.


Ruby

Ruby is the red variety of the mineral called corundum, which is composed of aluminium oxide (any other colour of corundrum is a sapphire). It is natural for rubies to have imperfections, including colour impurities and inclusions of rutile needles known as “silk”. The name “ruby” comes from the Latin for red, which is “ruber”. Natural occurring rubies are very rare and are extremely rare in large sizes over 3ct.


Sapphire

Sapphire is any colour of the mineral corundum other than red (those are called ruby). Sapphires are mainly known for their shades of blues, but they come in an assortment of colours across the spectrum, including white and black.


Tanzanite

Tanzanite is part of the zoisite mineral species and is only found in East Africa. Tanzanite may be colourless, yellow-green, brown, or blue to violet when found; most stones are artificially heat treated to enhance their colour. Tanzanite is a brittle stone and although it can be worn daily, care should be taken to protect it from knocks, pressure and extreme temperature changes.


Topaz

The word “topaz” comes from the Greek word “Topazion” a Red Sea Island often covered in mist. The colour of topaz varies in a broad range of yellow, blue, pink, peach, gold, green, red, and brown, and it is often heat treated to change or enhance its colour.


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