Black tourmaline Chalcedony nodules This makes them pretty forgiving

This makes them pretty forgiving for new keepers who are trying to learn how to maintain a steady humidity for their isopod enclosures

revealing the radial pattern of crystal growth

They were prolific from this locale back in the 1990s

the availability of silica that is the basis for the quartz family

or in a desert terrarium

Black tourmaline Chalcedony nodules This makes them pretty forgivingLocale: Erongo Mountain, Namibia Approx dimensions: 3 x 2. 5 x 2. 5" Approx weight: 287g ** Loose piece on base This statuesque piece of black tourmaline, known as schorl, has the mercedes termination and glossy high luster characteristic of the Erongo region. The piece is effectively three intergrown crystals in a stepped formation, with partial crystals attached at one end. The sides are beautifully striated on the partial crystals, with more