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- A crystallized rock,
typically porphyritic, having hairline fractures that
contain copper and other metals.
- A large body of rock, typically porphyry, that contains disseminated
chalcopyrite and other sulfide minerals. Such deposits are mined in bulk
on a large scale, generally in open pits, for copper and byproduct
molybdenum. Most deposits are 3 to 8 km across, and of low grade (less
than 1% Cu). They are always associated with intermediate to felsic
hypabyssal porphyritic intrusive rocks. Distribution of sulfide minerals
changes outward from dissemination to veinlets and veins. Supergene
enrichment has been very important at most deposits, as without it the
grade would be too low to permit mining. AGI
Source:
Dictionary of Mining, Mineral, and Related Terms
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