For semiprecious beads and pendants that are beautifully mottled by Mother Nature, choose from mahogany obsidian beads and snowflake obsidian beads (aka flowering obsidian). Obsidian (pronounced ub-SIH-dee-in) is a natural glass that forms from volcanic activity. The gemstone is made of the same minerals as granite, but cooled so quickly that the minerals did not have time to crystallize. Some inclusions can be bubbles or crystals, creating random patterns, such as snowflake patterns. Obsidian is somewhat fragile, and is only slightly harder than window glass. It scratches easily and sharp blows can crack it. Do the lack of crystalline structure, it fractures in sharp curves, hence obsidian was used to make sharp tools as early as 21,000 B.C. Native North Americans used it in arrowheads, and the Aztecs used obsidian in sacrificial knives and mirrors. Obsidian has also been used in jewelry for centuries - keep the tradition alive!