Specimen of the month from the KGS collection: Cactus amethyst
Cactus amethysts are rare, found in only one place on Earth, in the Magaliesberg Mountains near Pretoria, South Africa. This specimen, on display in the foyer of the Mining and Mineral Resources Building, has been a part of the KGS collection for many years.
These crystals are quartz with amethystine (purple) coloring in them. Other specimens of cactus amethysts can range from clear to smoky, citrine (yellow), or iron-stained coloring.
The usual occurrence is of one large, perfectly formed quartz crystal that has a pyramidal shape on the end and contains additional smaller twinned quartz crystals with faceted terminations on each hexagonal side of the main crystal. These twinned crystals produce the “cactus” or prickly appearance around the main crystal.
This specimen consists of a cluster of nine to ten 2-inch crystals that formed with the faceted terminated quartz crystals with the amethystine coloring. When a bright light is shined on the specimen, its brilliant coloration is amplified by the hundreds of faces on the numerous crystals.
Although cactus amethysts are rare, they are bought and sold on many mineral sites. The deeper the amethystine coloring, the more valuable the specimen. Sometimes they are used in the metaphysical community as healing crystals and nature stones, and to promote wellness. They are sometimes called spirit stones or angel quartz.