Crushed Black Tourmaline Fine Powder - Natural GemstoneBlack tourmaline (schorl) is a crystalline mineral known for its striated structure and very dark, near black color distinct from obsidian's volcanic glass. Our fine grind black tourmaline powder delivers a consistent very dark, near black particle for craft and art applications. For Jewelry Makers & Craft Artists Fine black tourmaline gives resin pieces a smooth, deep dark tint. Ideal for layered resin work, gradient pours, and projects where a