Properties
Chemistry: SiO2
Color: Violet, Redviolet
Crystal system: Trigonal
Mohs Scale hardness: 7
Refractive index: 1,544-1,553
Birefringence: +0,009
Specific gravity: 2,63-2,65
Information
Can be confused with
Beryl, Flourite, Kunzite, spinel, topaz, tourmaline and colored glass. There is also an abundance of synthetic quartz on the gemstone market, nowadays.
Treatments
Heat treatment in 470-775 degrees celsius renders light yellow, red-brown, green or colorless varieties. Some amethysts can lose colour in daylight. Original color can be restored with X-ray. The trace element that gives the amethyst its colour is Iron (Fe).
Instruments for identification
Microscope / loupe to observe colour changes and inclusions. Synthetic material is often free from inclusions and more evenly coloured.
Polariscopes and conoscopes are particularly useful for all types clear quartz. With these instruments it's possible to do a kind of diagnostic test of quartz.
Refractometre, measuring the refractive index and double refraction are importent.
Known deposits
May be found in geodes of alluvial origin. The most significant deposits can be found in Brasil, Madagascar, Zambia, Uruguay, Russia amongst others.
Miscellaneous:
Amethyst is one of the most popular variants of quartz. In Sweden it´s history go back to the vikings.
Read/learn more about Amethyst
Gemstone Guides & Knowledge
Read more about Amethyst on RIDDGEM Blog
Watch movies and Shorts about Amethyst on RIDDGEM YouTube
Amethyst in healing (Source: ChatGPT)
Amethyst is a popular crystal in healing and spiritual practices, known for its calming and protective properties.
Read/Learn more about Amethyst - Healing Properties
