amorphous
Snowflake obsidian
- Crystal system
- amorphous
- Hardness
- 5–6 on the Mohs scale
- Lustre
- vitreous
- Colour
- Black with grey-white radiating patches
- Where it forms
- As obsidian, followed by partial devitrification: over time the unstable glass begins to organise itself into crystals, and it does so in radiating spherulites.
- Chiefly from
- Utah, United StatesMexicoArmenia
Why it is that colour
The white flecks are cristobalite — a genuine silica mineral — that has crystallised out of the glass. The stone is caught partway through turning from glass into rock.
Safety
As obsidian — sharp when broken. Cristobalite dust is a particularly hazardous form of crystalline silica, so cutting this material warrants more care than most.
Where it comes from
Common and cheap, chiefly from Utah and Mexico.
Historical use
No distinct history from obsidian.
Recorded as history and attributed where possible. That a stone was used for something establishes that people used it, not that it worked.
What is attributed to it, and since when
No traditional history distinct from obsidian generally. Its meanings are modern and derived from the appearance.
Described, not endorsed. Dating a claim is not the same as assessing it — but an association that first appears in a book published in 1985 is not an ancient inheritance, whatever the label says. A sincere account of feeling better is compatible with the stone doing nothing — see the placebo effect.
Worth knowing
The snowflakes are the stone dying. Glass is thermodynamically unstable — the atoms are frozen in a disordered arrangement they would rather leave — and over long periods they migrate into ordered crystal patches. Each white flower is a spherulite of cristobalite, growing outward from a nucleation point.
Given enough time the whole thing would become rock. What is being sold is an intermediate state in a process that started when the lava cooled and has not finished.
Identity checked against IMA-CNMNC master list, June 2025.