Black Obsidian Lot Mexico (mini tumbled stone XXS) - 100g

OBSN-XXS-02
Origin: Mexico
Grade: AA

Obsidian is a silica-rich volcanic rock. Different types of obsidian exist, differing due to the rock's chemical composition. Obsidian is actually a natural glass. It forms during an eruption of silica-rich lava with less than 3% water. Upon exiting the volcano, it cools very rapidly, freezing the crystallization process.

This can be compared to a piece of lava suddenly solidifying as it emerges from a volcano. The direct consequence of this phenomenon is the inability of the rock to crystallize. The result is the creation of a volcanic glass with a uniform texture, which is referred to as an amorphous mineral. Furthermore, obsidian has sharp edges and very fine blades. It is a natural mineral with a complex composition.

Thus, obsidian is essentially composed of silicon dioxide, about 70% or more. Its fracture is conchoidal (i.e., furrowed with curved and concentric striations) and its hardness is 5 to 5.5 on the Mohs scale. It has different colors and different reflections due to the volcano where it was discovered and its various inclusions. It should be noted that each deposit, linked to a volcano, provides a different obsidian.