Exploring the Selenite: A Deep Dive into the Gem-A Collection of Gemstones and Minerals
In the fascinating realm of gemstones, selenite stands out for its unique properties and rich history. This colorless variety of gypsum, not containing selenium, was first named by J.G. Wallerius, a Swedish scientist, in his 1747 book Mineralogia, eller Mineralriket.
Selenite, named after Selene, the Greek goddess of the Moon, is known for its moon-like pale reflection. This brittle stone, with a hardness of only 2 on Mohs' scale, is not suitable for faceting but can be beautifully carved as cabochons or beads due to its softness.
Selenite crystals, often tabular with a rhombus shape, form in sedimentary rocks, specifically limestone. They can be lightly colored due to inclusions or impurities, displaying pale pastel tints. The specimen of selenite in the Gem-A Gems & Mineral Collection, for instance, has a green hue due to copper-based mineral inclusions.
The world's largest known crystals of selenite can be found in the Cave of Crystals in the Naica mine in Chihuahua, Mexico. These crystals, some as large as 1.2m in diameter and 15m in length, are truly awe-inspiring.
In the Middle-Ages, selenite was discovered in abundance in Germany in the region of Gotha and was used as a substitute glass pane to protect pictures of the Virgin Mary, becoming known as Marienglas.
Selenite has two distinct cleavage directions, making it a brittle stone. However, this didn't deter the Romans who, in antiquity, used transparent selenite as window panes before the invention of glass panes. In the Circus Maximus, selenite was used to create a glittering, sparkling effect during races by scattering powdered selenite on the ground.
Plinius the Elder referred to selenite as specularis lapis or 'mirror-like stone'. This moniker still holds true today, as selenite continues to captivate us with its shimmering beauty.
For those with a passion for gemmology, Gem-A offers workshops and courses to deepen your understanding of this captivating mineral. One can also become a Member of Gem-A to receive the magazines, Gems&Jewellery and The Journal of Gemmology, filled with fascinating insights into the world of gemstones.
Whether admired for its historical significance, its unique properties, or its radiant beauty, selenite remains a captivating gemstone that continues to intrigue and inspire.
[1] Wallerius, J.G. (1747). Mineralogia, eller Mineralriket. [2] Mineralogia, eller Mineralriket. (n.d.). Retrieved from https://www.britannica.com/topic/Mineralogia-or-Mineralriket
This article was originally posted on 18-04-2019.
- For those captivated by the intricacies of gemmology, Gem-A offers a variety of courses and workshops to deepen your understanding of selenite, a captivating mineral with a rich history.
- In addition to courses, joining Gem-A as a Member allows access to publication gems such as Gems&Jewellery and The Journal of Gemmology, featuring insights into selenite's properties and its role in science, health-and-wellness, and more.
- Beyond its historical significance and unique properties, selenite is also a subject of interest in the realm of publications, with seminal works like Mineralogia, eller Mineralriket shedding light on its origins and natural occurrence.
