Tourmaline, Schorl cluster - Minas Gerais, Brazil (MS2902c)

Discrete Tourmaline crystals have inter-grown into a hand-sized specimen weighing about 60 grams and measuring about 55mm x 30 mm x 25mm.  Other minerals, such as feldspars add contrasting color.  The yellow cube is a typical bouillon cube, measuring about a half-inch on a side, photographed for size reference.