Volcanic glass · Mohs 5–5.5

Obsidian

Rapidly cooled volcanic glass rather than a crystalline mineral. Can fracture into sharp edges; retire damaged beads.

Composition

Silica-rich volcanic glass

Hardness

5–5.5 on the Mohs scale · scratch resistance, not toughness

Birthstone

No modern month assignment

Care

Clean gently with a soft cloth and mild soapy water; rinse briefly and dry. Avoid heat, chemicals, ultrasonic cleaning and hard impacts. Ask about treatments before cleaning.

Paired with

Scorpio

Symbolic

Grounding · Root chakra. Design vocabulary, not a physical effect.