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Semi Precious Stone Topaz

It is a fluorine aluminium silicate and comes in yellow, yellow-brown, honey-yellow, flax, brown, green, blue, light blue, red and pink … and sometimes it has no color at all. The topaz.

The topaz has been known for at least 2000 years and is one of the gemstones which form the foundations of the twelve gates to the Holy City of the New Jerusalem. These so-called apocalyptic stones are intended to serve in protection against enemies and as a symbol of beauty and splendour. It cannot be proved conclusively whether the name of the topaz comes from the Sanskrit or the Greek, though the Greek name ‘topazos‘ means ‘green gemstone’. The Romans dedicated the topaz to Jupiter.

The colour in which the topaz is most commonly found is yellow, and that is the colour in which it occurs in one of the major German gemstone rocks, the Schneckenstein (a topaz-bearing rock said to resemble a snail) in Saxony. In the 18th century, it was mined there during a period of over 60 years. However, most of the crystals were hardly a centimetre in diameter. You had to go to Siberia or Brazil to find crystals as large as your fist. Having said that, anyone who is interested can convince himself of the beauty of cut specimens in the topaz set in Dresden’s Grünes Gewölbe (Green Vault). The enormous and magnificent topaz from the Portuguese crown, the Braganza, was for a long time thought to be a diamond. It weighs 1680 ct..

In mysticism, the topaz is attributed with a cooling, styptic and appetising effect. It is said to dispel sadness, anger and nocturnal fears, to warn its wearer of poisons and protect him or her from sudden death. It is reputed to make men handsome and intelligent and sterile women fertile and happy. However, it is probably better not to rely too much on its magical powers, since it was also claimed that you could immerse your hand in boiling water after a topaz had been thrown into it and retract it again unharmed! It is the stone of the month November.

In the Empire style, the topaz was still widespread, but then the more reasonably priced citrine took over from it and even usurped its name – gold topaz. Since then, the topaz has been a rather exotic figure in the jewellery trade, and has been given the additional predicate ‘pure’ to make it clear that the topaz, not the quartz topaz, is meant. And it is still waiting for its well deserved comeback to this day.

Blue Saphhire

Color in gemstones breaks down into three components: hue, saturation, and tone. Hue is most commonly understood as the “color” of the gemstone. Saturation refers to the vividness or brightness or “colorfulness” of the hue, and tone is the lightness to darkness of the hue. Blue sapphire exists in various mixtures of its primary and secondary hues, various tonal levels (shapes) and at various levels of saturation (brightness): the primary hue must, of course, be blue.

Blue sapphires are evaluated based upon the purity of their primary hue. Purple, violet and green are the normal secondary hues found in blue sapphires. Violet and purple can contribute to the overall beauty of the color, while green is considered a distinct negative. Blue sapphires with no more than 15% violet or purple are generally said to be of fine quality. Blue sapphires with any amount of green as a secondary hue are not considered to be fine quality Gray is the normal saturation modifier or mask found in blue sapphires. Gray reduces the saturation or brightness of the hue and therefore has a distinctly negative effect.

The color of fine blue sapphires can be described as a vivid medium dark violet to purplish blue where the primary blue hue is at least 85% and the secondary hue no more than 15% without the least a mixture of a green secondary hue or a gray mask.

The 422.99 carats (84.60 g) Logan sapphire in the National Museum of Natural History, Washington D.C. is one of the largest faceted gem-quality blue sapphires in the world.

Star Sapphire

A star sapphire is a type of sapphire that exhibits a star-like phenomenon known as asterism. Star sapphires contain intersecting needle-like inclusions (often the mineral rutile, a mineral composed primarily of titanium dioxide) that cause the appearance of a six-rayed ‘star’-shaped pattern when viewed with a single overhead light source.

The value of a star sapphire depends not only on the carat weight of the stone but also the body color, visibility and intensity of the asterism.

The Star of India is thought to be the largest star sapphire in the world and is currently on display at the American Museum of Natural History in New York City. The 182 carat (36.4 g) Star of Bombay, housed in the National Museum of Natural History, Washington D.C., is a good example of a blue star sapphire.