Amethyst Geological Facts
Amethyst is a variety of quartz, or silicon dioxide (SiO2). It is identified by its striking purple shade, ranging from the palest lilac with hints of pink to the deepest shades of violet and indigo.
Amethyst gets its colour from trace amounts of irradiated iron. This radiation emanates from within the earth, and gamma rays from this radiation emanate into the quartz crystal. The rays ‘knock’ single electrons from an iron lattice into the forming crystal structure, causing colouration in the quartz. This process is documented as an “O2- -> Fe4+ charge transfer process” (Epstein, 1988).
As it is a member of the quartz family, it has a specific gravity (sp. gr.) ratio, or density, of 2.65, and a Mohs hardness rating of 7.
These faces repeat in series of six-sided, or hexagonal prisms, and bordered by hexagonal pyramids. It has a vitreous lustre, which means it reflects light with a glassy quality (Allaby, 2013). The refractive index of amethyst ranges from 1.543–1.553.
Amethyst is found all over the world, in igneous, metamorphic and clastic rocks, and can also be found in mineral veins. There are deposits of quartz all over the world, with amethyst historically found in the Ural Mountains of Russian Siberia. This prominence of amethyst gave the crystal the name of its quality grading system, with the highest quality amethysts graded as Siberian or “Deep Russian” in quality.
Currently, amethysts are mined all over the world, with extensive quarries in South American countries, with Brazil considered “the most important source of amethyst in the world” (Epstein 1988). Amethyst quarries abound in North America as well, with hundreds across the United States and dozens across Central America. Europe is abundant with quartz deposits, with several mines located throughout Asia and Oceania.
Amethysts can be synthetically heat-treated to fade its purple colour to a subtler, less vivid shade, or altogether transform it into another colour. Between 300-400°C, amethyst can lose its purple colour and take on duller tones, orange, yellow or brown. Yellow quartz, or citrine, is produced naturally and synthetically by applying heat to amethyst (Epstein 1988).
Amethyst is mined in the form of geodes or hollow “earth-like” formations within sedimentary and volcanic rock structures. Amethyst can be purchased in its raw, untreated form, and these geodes can range from grams to hundreds of kilograms in weight. Geodes can be cut down in size and sold in more cost-effective weights as raw or rough crystals, chunks, or later polished to highlight the quality and lustre of the amethyst within. Amethysts can be cut and polished for use in jewellery making or tumbled to form a smooth, pebble-shaped stone.
Amethysts through the Ages
Due to its geological prominence all over the world, amethyst has held significance in many cultures as a crystal with protective traits. According to the Greeks, amethyst would shield you from drunkenness. Eastern spirituality had similar ideas that amethyst could enhance the mental and spiritual abilities of the bearer, and aid in achieving a focussed, meditative state.
The ancient Egyptians prized amethyst greatly, with evidence of a ‘legitimate trade’ economy existing throughout the Bronze Age Aegean (Phillips, 2009). These crystals were mined from the Wadi el-Hudi quarry in the Eastern Desert of Egypt and traded extensively throughout the Aegean, carved in various cultural styles.
The tombs of the Pharaohs Djer and Tutankhamen, and Queen Mereret, all contained amethyst jewellery carved with scarabs, a symbol of immortality and resurrection, while Mycenaen and Minoan ruins revealed polished amethyst ‘seals’ engraved with markings characteristic of the era.
The Greeks believed that the dark, wine-coloured crystal could act as a talisman or amulet, and protect the wearer from the intoxicating effects of wine (Smith 1913). The Romans believed similarly, and went even further, to carve whole goblets and chalices from the crystal, hoping to protect the wealthy drinker from a nasty hangover.
The associations with amethyst and sobriety, clear-headedness and mental clarity grew stronger in the Medieval period, as the Church inlaid the gems into ecclesiastical or episcopal rings, worn by bishops. The choice for amethyst over any other precious gemstone or crystal harkens back to a tale in the Bible, specifically, the first Pentecost. On the 49th day after Easter, Jesus ascended into heaven, while the disciples gathered around him suddenly spoke new languages. Onlookers thought they were drunk, but they were instead blessed by the Holy Spirit to spread the gospels to new people. The Church chose amethyst to serve as a symbol for powers of communication, and clear thinking, in addition to the physical ideas of abstinence and sobriety from mind-altering or inebriating substances.
Owing to its’ rich and vivid colour, amethyst has also been used extensively as a gemstone to indicate royalty. Purple is quite literally, a rich and expensive colour, and developed by the Phoenicians in Tyr, Lebanon, as early as 1570 BCE, using a sea snail called a “murex.” The Phoenicians would recover Murexes by the thousands, and yield a deep red-indigo dye that would become known as “Royal Purple.” As such, royals throughout history have used shades of purple in their clothes, and in their jewels, to illustrate their wealth and power.
Amethyst was originally one of the ‘cardinal gemstones,’ considered precious and equal to emerald, sapphire, ruby and diamond. This was until the early 19th century when it was discovered to be abundant in Brazil, and the market was flooded with high-quality amethyst at wholesale price.
Amethyst is also found in the Himalayan mountains of Tibet, and was used in Tibetan Buddhist spiritualism as the crystal of choice for meditative prayer beads, or ‘malas.’ Due to its rich violet shade, they symbolized the crown chakra, a point of energy within the body focused on ‘awareness and intelligence’ (Stetler 2016), and ‘spiritual realisation’ (O’Sullivan, 2010).
These beliefs still exist in contemporary spirituality today, and amethyst is used for meditative, spiritual, and aesthetic purposes.
Cultures from all over the world have held beliefs about amethyst, influencing the use and value of the crystal. Over time, amethysts have had associated with them, beliefs of luxury, protection, sobriety, clarity, lucidity, intelligence, mental precision and wealth.
Allaby, M. (2013a). Quartz. In A Dictionary of Geology and Earth Sciences. Oxford University Press. http://www.oxfordreference.com/view/10.1093/acref/9780199653065.001.0001/acref-9780199653065-e-6907
Allaby, M. (2013b). Trigonal. In A Dictionary of Geology and Earth Sciences. Oxford University Press. http://www.oxfordreference.com/view/10.1093/acref/9780199653065.001.0001/acref-9780199653065-e-8738
Amethyst: Mineral information, data and localities. (n.d.). Retrieved 28 June 2020, from https://www.mindat.org/min-198.html
Andrews, E. (2016.). Why is purple considered the color of royalty? HISTORY. Retrieved 28 June 2020, from https://www.history.com/news/why-is-purple-considered-the-color-of-royalty
Epstein, D. S. (1988). Amethyst Mining in Brazil. Gems & Gemology, Winter. https://www.gia.edu/doc/Amethyst-Mining-in-Brazil.pdf
Kunz, G. F. (1911) Curious Lore of Precious Stones. Farlang. Retrieved 28 June 2020, from http://farlang.com/books/george-frederick-kunz-curious-lore-of-precious-stones
O’Sullivan, T. (2010). Chakras. In D. A. Leeming, K. Madden, & S. Marlan (Eds.), Encyclopedia of Psychology and Religion (pp. 134–136). Springer US. https://doi.org/10.1007/978-0-387-71802-6_104
Oxford English Dictionary. (n.d.). ‘amethyst, n.’. https://www.oed.com/view/Entry/6366?redirectedFrom=amethyst&
Phillips, J. (2009). Egyptian Amethyst in the Bronze Age Aegean. Journal of Ancient Egyptian Interconnections, 1(2), 9–25. https://doi.org/DOI:10.2458/azu_jaei_v01i2_phillips
Smith, M. N. (1913). Diamonds, pearls and precious stones. Printed for Smith Patterson company by Griffith-Stillings press. //catalog.hathitrust.org/Record/009597538
Stelter, G. (2016, October 4). Chakras: A Beginner’s Guide to the 7 Chakras. Healthline. https://www.healthline.com/health/fitness-exercise/7-chakras