Malachite is a crafting component introduced in the Blood and Wine expansion that can be dismantled into unrefined copper ore. It is not needed to craft anything.
It can be found as random loot or purchased from the following merchants:
- Armorer in Hauteville
- Blacksmith at Ardaiso Quarry
- Blacksmith in Belgaard Manor, after he is rescued
- Lazare Lafargue in his workshop
- Trentin in his workshop in Hauteville