Sunday, 2 July 2017

Amethyst by Cartier

Amethyst is a purple variety of quartz (SiO2) and owes its violet color to irradiation, iron impurities, and the presence of trace elements. Amethyst occurs in primary hues from a light pinkish violet to a deep purple. The best varieties of amethyst can be found in Siberia, Sri Lanka, Brazil and the far East. The ideal grade is called "Deep Siberian" and has a primary purple hue of around 75–80%, with 15–20% blue.
Amethyst can fade if overexposed to light sources and can be artificially darkened with irradiation. Amethyst was used as a gemstone by the ancient Egyptians and was used in antiquity for intaglio engraved gems. Synthetic amethyst is made to imitate the best quality amethyst. Its chemical and physical properties are the same to that of natural amethyst and it can not be differentiated without advanced gemmological testing.