|
| Alexanderite |
|
| This rare gemstone is named after the Russian tsar Alexander II (1818-1881), the very first crystals having been discovered in April 1834 in the emerald mines near the Tokovaya River in the Urals. The discovery was made on the day the future tsar came of age. Although alexandrite is a relatively young gemstone, it certainly has a noble history. Since it shows both red and green, the principal colours of old Imperial Russia, it inevitably became the national stone of tsarist Russia. |
| Amethyst |
|
| Its color is unparalleled, and even other, more expensive purple gemstones are often compared to its color and beauty. Although it must always be purple to be amethyst, it can and does have a wide range of purple shades. Amethyst can occur as long prismatic crystals that have a six sided pyramid at either end or can form as druzes that are crystalline crusts that only show the pointed terminations. As a mineral specimen, amethyst is popular for its color and nice crystal shapes that produce a handsome, purple, sparkling cluster. However, amethyst is not the same everywhere. Different localities can produce a unique amethyst to that particular region or even to that particular mine. Experts can often identify the source mine that a particular amethyst came from. The key to this is the specimen's color, shape of crystal, inclusions, associations and character of formation. The following is a list of many of the more noteworthy localities and some of the attributes that characterize the amethyst found there |
| Ametrine |
|
| Ametrine, also known as trystine or by its trade name as bolivianite, is a naturally occurring variety of quartz. It is a mixture of amethyst and citrine with zones of purple and yellow or orange. Almost all commercially available ametrine is mined in Bolivia, although there are deposits being exploited in Brazil and India.
The colour of the zones visible within ametrine are due to differing oxidation states of iron within the crystal. The different oxidation states occur due to there being a temperature gradient across the crystal during its formation.
Artificial ametrine can be created by differential heat treatment of amethyst.
Legend has it that ametrine was first introduced to Europe by a conquistador's gifts to the Spanish Queen, after he received the Anahi mine in Bolivia as a dowry. |
| Andalusite |
|
| is an aluminium nesosilicate mineral with the chemical formula Al2SiO5.
The variety chiastolite commonly contains dark inclusions of carbon or clay which form an X or a cross in section.
A clear variety first found in Andalusia, Spain can be cut into an interesting gemstone.[2] Faceted andalusite stones give a play of red, green, and yellow colors that resembles a muted form of iridescence, although the colors are actually the result of unusually strong pleochroism. |
| Andesine |
|
| Andesine |
| Apatite |
|
| Apatite is infrequently used as a gemstone. Transparent stones of clean color have been faceted, and chatoyant specimens have been cabochon cut.[1] Chatoyant stones are known as cat's-eye apatite,[1] transparent green stones are known as asparagus stone,[1] and blue stones have been called moroxite.[3] Crystals of rutile may have grown in the crystal of apatite so when in the right light, the cut stone displays a cat's eye effect. Major sources for gem apatite are[1] Brazil, Burma, and Mexico. Other sources include[1] Canada, Czechoslovakia, Germany, India, Madagascar, Mozambique, Norway, South Africa, Spain, Sri Lanka, and the US. |
| Aquamarine |
|
| Aquamarine (Lat. aqua marina, "water of the sea") is a gemstone-quality transparent variety of beryl, having a delicate blue or turquoise color, suggestive of the tint of seawater. It's closely related to the gem emerald. Colors vary and yellow beryl (heliodor), rose pink beryl (morganite), and white beryl (goshenite) are known |
| Chrysoberyl |
|
|
| Chrysoprase |
|
|
| Citrine |
|
|
| linohumite |
|
|
| Diamond |
|
|
| Emerald |
|
|
| Fluorite |
|
|
| Goshenite |
|
|
| Heliodor |
|
|
| Idocrase |
|
|
| Indicolite |
|
|
| Iolite |
|
|
| Jade |
|
|
| Kunzite |
|
|
| Kyanite |
|
|
| Labradorite |
|
|
| Malachite |
|
|
| Moonstone |
|
|
| Morganite |
|
|
| Orthoclase |
|
|
| Peridot |
|
|
| Petalite |
|
|
| Pezzottaite |
|
|
| Prehnite |
|
|
| Rhodonite |
|
|
| Rubellite |
|
|
| Ruby |
|
|
| Sapphire |
|
|
| Scapolite |
|
|
| Sphene |
|
|
| Spinel |
|
|
| Sunstone |
|
|
| Tanzanite |
|
|
| Tourmaline |
|
|
| Tsavorite |
|
|
| Zircon |
|
|
| Zultanite |
|
|
|
