This Specimen has been sold.
1.23" Black Tourmaline (Schorl) & Feldspar - Namibia
Here is a sharp group of schorl crystals sitting on some beautifully terminated feldspar crystals from the Erongo Mountains in Namibia. Although the crystals have broken away from the original host rock, the specimen displays nicely on a flat surface.
Tourmaline is a crystalline boron silicate mineral compounded with elements such as aluminium, iron, magnesium, sodium, lithium, or potassium. Schorl, or black tourmaline, is the most common form of tourmaline, and has been used for everything from jewelry to piezoelectric guitar pickups.
Feldspars are a group of rock-forming tectosilicate minerals. It is also one of the most common minerals on earth, making up nearly 60% of the crust.