Snowflake obsidian from Mexico
Size-
5.7cm x 3.7cm x 2.5cm
Weight-
59g
You will receive the item in the photo
Snowflake obsidian is a natural volcanic glass featuring distinctive gray-to-white radial crystal clusters that resemble snowflakes.
Crystal system- Amorphous (it lacks an ordered internal atomic structure because it is a supercooled glass). How ever,the “snowflake “ inclusions consist of micro-crystals of cristobalite (a high temperature silica polymorph) which individually possess a tetragonal crystal structure.
Mineral class - classified as a mineraloid rather then a true mineral,because its overall structure is non-crystalline.
Hardness- 5-5.5 on MOHs scale.
Rock formation:
Rock type- Extrusive igneous rock,
Formation process- forms when silica rich felsic (holistic) lava cools rapidly at the margins of a lava flow,preventing large scale mineral nucleation.
The snowflakes- over thousands to millions of years,the unstable volcanic glass undergoes a slow aging process called devitrification ,during which microscopic clusters of needle like cristobalite grow radially inside the dark glass matrix to create the characteristic white patterns.
