Olivine and Obsidian
Subcategories
Obsidian is volcanic glass, which does not form crystals and occurs in different colorations. Base is black obsidian, which can include white flakes or iridescent color. Mahogany obsidian has a brown color with black spots ... more visit aimed at Obsidian
Olivine or Peridot is also green translucent gemstone that is found in crystals of rather small size .. more about Peridot