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. Clear obsidian contains very few opaque impurities or microscopic mineral crystals. Other colors generally result from tiny crystals of feldspar, or inclusions of iron oxide or a wide variety of other minerals that may be present in volcanic flows. Shimmering, dramatic golden obsidian is produced by bubbles in the lava flow where this obsidian was mined. For semiprecious beads and pendants that are beautifully patterned, choose from mahogany obsidian beads and snowflake obsidian beads (aka flowering obsidian). Over a long period of time, obsidian can gradually change from glass to rock. This is known as "devitrification." The silica molecules in the volcanic glass slowly rearrange into organized crystal patterns such as the "snowflakes" of quartz crystals that are found in snowflake obsidian.
Usually black or dark gray with light gray patches, semiprecious snowflake obsidian beads, donuts, and pendants are believed to assist with clarity and logic. Obsidian is somewhat fragile, and is only slightly harder than window glass. It scratches easily and sharp blows can crack it. Due to the lack of crystalline structure, it fractures in sharp curves, hence obsidian was used to make sharp tools as early as 21,000 BCE. 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!