Judging quality
Malleable — it bends rather than breaks — and shows a bright salmon metal under the brown patina. Usually part-covered in green malachite film.
Element
Native Copper
Metallic copper that crystallised directly out of hydrothermal fluid, growing in twisted branching sprays and flattened arborescent plates. Michigan's Keweenaw deposits produced masses weighing tonnes.
Care
Patinates naturally. Leave it or lightly wax; harsh cleaning strips the character and the value.
History & lore
Old Copper Complex peoples of the Great Lakes were cold-working native copper into tools 6,000 years ago, some of the earliest metalwork anywhere.
Cultural history, recorded as tradition rather than as medical or scientific claim.
Common questions about Native Copper
- What is Native Copper?
- Metallic copper that crystallised directly out of hydrothermal fluid, growing in twisted branching sprays and flattened arborescent plates. Michigan's Keweenaw deposits produced masses weighing tonnes.
- How hard is Native Copper and what is it made of?
- Native Copper is a Element-family mineral with the composition Cu. It crystallizes in the cubic system and rates 2.5-3 on the Mohs hardness scale. It occurs in bronze, red, green.
- Where does Native Copper come from?
- Notable localities for Native Copper include Keweenaw Peninsula, Michigan, USA, Arizona, USA, Bolivia, Namibia.
- How do you tell good Native Copper from filler?
- Malleable — it bends rather than breaks — and shows a bright salmon metal under the brown patina. Usually part-covered in green malachite film.
- How do you care for Native Copper?
- Patinates naturally. Leave it or lightly wax; harsh cleaning strips the character and the value.
See it in person
Photographs only go so far
Both rooms are open six days a week, and there is always someone happy to pull pieces out of the case so you can compare them under the light.