Arsenic (Native)
Arsenic (Native) is native element (semi-metal), As. In the hand, it rates 3.5 on the Mohs scale, and it runs tin gray fresh and dark gray to black tarnish. Heavy gray botryoidal masses with onion-skin layers that tarnish nearly black, fresh breaks briefly flash metallic then dull within days. Hydrothermal veins; notable: Erzgebirge (Germany/Czechia), Japan, Morocco.
The geology.
Arsenic (Native) carries the formula As. It belongs to the trigonal system. The trade files it under native element (semi-metal).
It sits at 3.5 on the Mohs scale. The surface reads metallic on fresh breaks, dulling fast. Light behaviour is opaque. Specific gravity runs 5.6 to 5.8. The streak is gray to black. It breaks with perfect basal cleavage; brittle.
Heavy gray botryoidal masses with onion-skin layers that tarnish nearly black, fresh breaks briefly flash metallic then dull within days.
Common cuts are botryoidal crusts, onion-layered masses or massive.
The origins.
Hydrothermal veins; notable: Erzgebirge (Germany/Czechia), Japan, Morocco.
On value, the database notes: collector-only specimen.
Traditional associations.
In energy work traditions, native arsenic has no positive lore and is kept strictly as a sealed collector curiosity.
Included for completeness. Tradition is worth knowing about, and it is worth keeping separate from the mineralogy.
Spotting the real thing.
Heavy gray botryoidal masses with onion-skin layers that tarnish nearly black, fresh breaks briefly flash metallic then dull within days.
| Looks like | How to tell them apart |
|---|---|
| Antimony (native) | Antimony stays brighter tin-white; arsenic darkens quickly |
| Hematite (botryoidal) | Hematite streaks red-brown; arsenic streaks gray |
| Arsenopyrite | Arsenopyrite is a brighter silvery crystal-former, harder, in distinct wedges |
At-home tests.
These checks cost nothing. Daylight, a 10x loupe and a little patience are the whole kit for arsenic (native).
| Test | What you should see |
|---|---|
| By eye | Onion-layer botryoidal habit |
| By eye | Heavy (SG ~5.7) |
| By eye | Tarnishes dark, display specimens stay dull |
If these checks leave you unsure, that is what appraisers are for. Do not file, heat or soak a piece to find out.
Care & handling.
At 3.5 on the Mohs scale this is a soft material. Keep it as a display piece, store it apart from harder stones, and skip daily-wear settings.
It breaks with perfect basal cleavage; brittle, which is worth knowing before you set it or drop it.
Most damage happens during cleaning, not wearing. Avoid steamers, ultrasonic tanks and anything from under the sink.
This IS arsenic: handle rarely and with gloves, keep sealed and labeled, wash hands, and never sand, heat, or display where children can reach.
A deeper look.
Extended detail on composition, sourcing, authentication and market value.
The physical record
The formula on record is As. Crystal system: Trigonal. Specific gravity: 5.6 to 5.8. Streak: Gray to black. Cleavage and fracture: Perfect basal cleavage; brittle.
How it reaches the market
Hydrothermal veins; notable: Erzgebirge (Germany/Czechia), Japan, Morocco.
What it gets confused with
Antimony (native): Antimony stays brighter tin-white; arsenic darkens quickly. Hematite (botryoidal): Hematite streaks red-brown; arsenic streaks gray. Arsenopyrite: Arsenopyrite is a brighter silvery crystal-former, harder, in distinct wedges.
What it is worth
Collector-only specimen.
One more thing
Old German miners called it 'Scherbenkobalt', goblin shards, blaming mountain spirits for ore that poisoned instead of paying.
An education-first guide.
There is nothing to buy on this page. Arsenic (Native) is not part of our catalogue, and the guide is here anyway because somebody searching the name deserves a straight answer.
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