Peridot: The Evening Emerald
Introduction
Peridot, celebrated as August’s traditional birthstone, has captivated hearts for millennia. The ancient Romans fondly referred to it as the ’emerald of the evening’ due to its unwavering vibrant green hue, even under artificial lighting. Historical records show that early Egyptian jewelry, dating back to the early 2nd millennium B.C., prominently featured peridot. These precious stones were sourced from a volcanic island in the Red Sea, which, after its rediscovery in the 20th century, has been depleted of its peridot reserves.
Composition and Appearance
Belonging to the Olivine mineral group, peridot shares an isomorphous crystal structure with its group members, though their chemical compositions vary. Peridot’s enchanting green shade is attributed to the presence of ferrous iron, further influenced by trace elements like Fe3+, Ti4+, and Ni2+. Specimens rich in magnesium exhibit a more coveted green shade, while those with higher iron concentrations lean towards a yellow-green or brownish-green hue.
Origins
While the volcanic island Zabargad (or St. John) in the Red Sea was historically a significant source of peridot, it has since been exhausted. Presently, peridot deposits are found in:
- Pakistan
- Myanmar (Burma)
- Vietnam
- Australia (Queensland)
- Brazil (Minas Gerais)
- China
- Kenya
- Mexico
- Norway (near Bergen)
- South Africa
- Sri Lanka (Ceylon)
- Tanzania
- United States (Arizona and Hawaii)
Properties and Enhancements
With a hardness of 6.5 – 7 on the Mohs scale, peridot is moderately durable.
Currently, there are no treatments known to enhance peridot’s appearance. While genuine lab-created peridot doesn’t exist, there are simulants in the market that mimic its captivating green hue.