Obsidian

Obsidian properties at a glance

Geology & background

Forms when volcanic lava cools rapidly with minimal crystal growth, creating natural volcanic glass.

One of the first materials used by humans for cutting tools, dating back to the Stone Age.

How to identify Obsidian

• Check whether the specimen's color and texture match typical Obsidian examples.
• Photograph a fresh surface in natural light and avoid shadows, glare, or wet surfaces.
• Use hardness, streak, luster, grain size, and locality together; no single trait is enough for every specimen.

Where Obsidian is found

Obsidian is reported from multiple localities or geological settings. Exact locality should be verified from specimen provenance, maps, or field notes.

How much is Obsidian worth?

Value depends on size, condition, color, crystal quality, locality, rarity, preparation, and provenance. Treat this as educational guidance, not an appraisal.

Common uses

• Jewelry
• Surgical scalpels
• Decorative objects
• Spiritual practices

Interesting facts

• Can be sharper than surgical steel scalpels
• Used by ancient peoples for weapons and tools
• Some obsidian contains tiny bubbles creating 'snowflake' patterns

Care & safety

Treat Obsidian as a collector specimen unless hardness, cleavage, and fracture are confirmed.

Avoid inhaling dust. Do not cut, grind, or polish unknown specimens without eye protection and a properly rated respirator.

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