Uses of Obsidian Rock

Historical Use

• Obsidian was used throughout antiquity as a cutting tool and an artistic material. Ever since it was first discovered, obsidian's unique, conchoidal reaction to fracture has made it ideal for cutting. Because it fractures into flakes, the edges that are formed are very smooth and very sharp. Stone-Age hunters used obsidian blades for tasks from cutlery to hunting and even warfare. Likewise, obsidian's conchoidal nature makes it ideal for jewelry and statue-making.

Modern Surgical Blades

• In modern times, obsidian often serves as a surgical blade. The way it fractures when broken even sloppily gives way to incredibly sharp edges. Subsequently, contemporary scientists have discovered how to sharpen obsidian edges into blades much, much sharper than standard surgical blades. While even the sharpest standard blades upon inspection under a microscope reveal rough, jagged teethlike edges, obsidian blades when viewed through microscopic inspection are still smooth. Because they lack these "teeth," obsidian blades barely damage skin tissues and are ideal for cosmetic surgeries.

Jewelry

• As a glass, obsidian has a beautiful sheen and color. As such, it has been used since the Stone Age as a source for jewelry. Obsidian often is used as a backing for pieces of jewelry with other gemstones. It can be polished to become highly reflective, especially when placed behind another gem, such as opal. As backing for the piece of opal, the polished obsidian will change the way the opal reacts to light at different angles. Obsidian typically is used for earrings and pendants.

Other Artistic Crafts

• The reflective and conchoidal characteristics of obsidian also make it useful and ideal for crafts other than jewelry and knife-making. Obsidian's hardness is low. At 5.5, it is easily broken or chipped. While this makes it not a great choice for, say, an engagement ring, obsidian often finds use as a stone for carving. Like craft makers of the Stone Age, contemporary artisans find obsidian useful for carving statues, pendants, medallions and other items. Furthermore, when polished, obsidian possesses a high luster. As such, it is sometimes used to make decorative, artistic mirrors.