Rock crystal is the purest form of quartz. It has a water-white complexion and in ancient times was believed to be made from un-meltable ice. To the untrained eye, cut and faceted rock crystal could be mistaken for a diamond. However, for those familiar with the two gemstones, the differences are stark due to their different crystal structures. Rock crystal does not have the same brilliance as cut diamonds, instead, it has a lustrous hexagonal prism with a vitreous lustre varying from waxy to dull.
Gemstones: Rock Crystal
Rock crystals are often large and can be used not only in jewellery, but also in decorative objects such as carved lamp stands or clocks. It is well suited to quartz clock cases due to its screw-like atomic formation which creates a piezo-electric effect.
Rock crystal is a very common mineral and therefore affordable in large quantities. It is found across the globe, from Brazil, Japan, Switzerland and the United States. Rock Crystal only has a rating of 7 on the Mohs scale, which makes it somewhat brittle but can easily be elaborately carved. In the medieval period rock crystal was often used as the casement for saints relics.
In the 1920-30s rock crystal had a renaissance in fine jewellery. The Art Deco Period embraced rock crystal for its clean crisp lines. Famous Parisian Maison’s, such as Cartier and Boucheron, used rock crystal carved into hard edged geometric shapes and typically set in white gold or platinum jewellery beside onyx, emeralds or rubies for a dramatic colour contrast.