Obsidian stone is found in "Russia" / "Arizona" / "Syria" / "Hasakah" and "Algeria",

It has many physical and chemical properties, including:

Physical properties

• The shape is mass / has no atomic structure
• Glass / Volcanic group
• Does not tolerate heat
• Hardness 5/5.5
• The color is black
• Translucent / Opaque
• Vitreous sparkle
• Double refractive shape

Chemical properties

• Refractive index 1.48 / 1.51
• Density is 2.35 / 2.60
• The chemical formula is silicon oxide