The Mahogany Obsidian handles of these Case knives are actually glass. Volcanic glass from Mexico to be more precise, formed by quickly cooling lava. Many of man's earliest tools were crafted from Obsidian. Ancient Native Americans used Obsidian to make arrowheads and spears, and for spiritualists, Mahogany Obsidian is a stone of strength. High iron content in the lava, and the crystallizing of other elements create the striking brown and black color of Mahogany Obsidian. Inlaid with nickel silver and amber, these are surely among the most beautiful Case knives ever built. It's only fitting that the Case craftsmen of today would make knives using Obsidian, the material favored by cutlers and tool makers centuries past.