This Specimen has been sold.
2.1" Botryoidal Prehnite - Mali
This is a 2.1" wide formation of translucent, botryoidal green prehnite, collected from the Kayes Region of Mali, Africa.
Prehnite is a calcium aluminum silicate with the chemical composition Ca2Al(AlSi3O10)(OH)2. It generally occurs as volcanic cavity infillings. It often displays colors between yellow and green, but colorless and blue specimens are not unheard of.