Chalcopyrite mineral is a major
It is not very rich in
But it is a major ore
because there is so much of it available.
It occurs in
hydrothermal veins, often together with another very common sulphide
mineral - pyrite.
It is yellower than
pyrite, and does not for cubic crystals like pyrite does.
It can be massive, or form crystals that are tetrahedal.