$400.00 €372 £320.00 approx. This specimen is priced in US dollars, all other prices are approximate.
A rich little example of chalcotrichite probably from Wheal Phoenix. It is interesting to see the history of this specimen. The is an old Tregeseal Barstow label that attributes the specimen as being from the Fowey Consols, but this has been reattributed as being from Wheal phoenix by Nick Carruth who is almost certainly correct because there was no malachite at Fowey Consols.