Obsidian, a common black gemstone, is a naturally occurring form of silica that is usually black in color.
Obsidian can be processed into arts and crafts.In addition, obsidian has the characteristics of glass, and the section of the broken shell is very sharp.Most obsidian jewelry today is produced in Central and North America, and Mexico is the national stone.
The formation process
Obsidian is a natural glaze formed by the sudden cooling of magma flowing from volcanic lava. It is a kind of amorphous gem. The main component of obsidian is silica (SiO2).
During formation, magma containing silica condenses quickly because the temperature outside the lava flow drops rapidly and cools fastest. Obsidian is usually found outside the flow or near the sea at the foot of a volcano.Because of its unique formation process, obsidian crystals also contain 1 to 2 percent water.
The origin
Obsidian is found mostly in once volcanic areas such as Hawaii in the United States, Japan, and Java in Indonesia, Iceland, Hungary, the Lipari Islands of Italy, the former Soviet Union, Mexico, Ecuador, and Guatemala.
The dark black one-eyed obsidian is found in Arizona and New Mexico in the United States. The Indians called it "tears of the Apache."
Most obsidian jewelry comes from Central and North America and is the national stone of the United States of Mexico.