Hi azgolfin, since malachite is a mineral and does have some property of copper it is possible. But I would think it would be more like what we call ground noise from mineralization if you got a response from a metal detector. So I would be hesitant to give you an absolute yes on your query. I know this probably didn't help any but it would be interesting to have a speciman to try it out on a metal detector. I'm glad you asked this and it is a good subject for discussion.
Ok azgolfin take care and if I can help you with anything else just PM me. God Bless ya and good luck and let us know about any results.
John Tomlinson,CET P=VI
John's Detectors
Blackwell,Tx.
Best Little Detector Shop in Texas!

