SCHORL on MUSCOVITE, Biermann (Bethel) quarries Fairfield Co. Connecticut USA (small cabinet)

Schorl, the sodium iron (divalent) endmember of the tourmaline group, is the most prevalent species, constituting 95% or more of natural tourmaline. Historical records indicate that the term "schorl" was already in use before 1400, derived from a village now called Zschorlau in Saxony, Germany. This village was named "Schorl" or similar variations and was located near a tin mine where black tourmaline, alongside cassiterite, was discovered.