Acanthite

Silver sulfide and the most important silver ore — a soft, black, sectile mineral.

Acanthite specimen — Photo: Ivar Leidus, CC BY-SA 4.0, via Wikimedia Commons

How to identify acanthite

Black to lead-gray, dull metallic.
Cuts like lead with a knife.
Very heavy.

Often confused with

Chalcocite
Chalcocite is lighter.
Compare side by side
Galena
Galena is brighter and cleaves into cubes.
Compare side by side

Where it's found

Guanajuato, Mexico
Freiberg, Germany
Comstock Lode, Nevada

Uses

Silver ore.

Rock tumbling

Not suitable for tumbling.

Did you know?

The black tarnish on silverware is a thin film of the same compound, silver sulfide.

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