One of the most valuable non-transparent stones used in jewellery, turquoise was one of the first rocks to be mined, even before the 4th millennium BC. Although various shades of blue, blue-green and greenish grey can be found, it is the strong sky blue which is the most valuable and which contrasts most strikingly with precious metals. Often the delicate veining of the host rock is apparent in the stone, and ‘Persian Turquoise’ is the name given to stones which do not display this veining, originally considered the finest. However, this feature is now often sought after as evidence of the stone’s authenticity, and so turquoise mined in the south-western United States, worked for centuries by American Indians, has become popular. The porcelain-like lustre is often shown off in a cabochon cut, with a low, gently rounded, polished surface.
Did you know?
- The name is from the French pierre turquoise, meaning Turkish stone; it was brought to Europe in the Middle Ages from the Eastern Mediterranean and Persia by Levantine traders.
- Turquoise is sometimes considered to be the birthstone for December.
- Turquoise jewellery is sometimes offered to celebrate an 11th wedding anniversary.
- The stone is considered sacred by North American Indians.