What is porphyry system?
Porphyry systems are universally typified by three main features: (1) presence of veins and veinlets forming stockworks, within which are disseminated sulphides of Fe, Cu, Mo, Pb and Zn, as well as native Au, and minerals of W, Bi and Sn; (2) the mineralisation is spatially and genetically related to intrusive bodies.
What is the importance of porphyry?
1 Introduction. Porphyry ore deposits are the Earth’s major resources of copper, molybdenum, and rhenium (Sillitoe, 2010) and also provide significant amounts of gold, silver, and other metals. Mineralization styles include stockwork veins, hydrothermal breccias, and wall-rock replacements.
What is a porphyry gold deposit?
Porphyry copper–gold deposits are large volume, low-grade disseminations formed by precipitation of copper and gold (plus molybdenum) from fluids of magmatic origin1.
What is porphyry mining?
In general, porphyry deposits are characterized by low grades of ore mineralization, a porphyritic intrusive complex that is surrounded by a vein stockwork and hydrothermal breccias. Porphyry deposits are formed in arc-related settings and are associated with subduction zone magmas.
How do you identify porphyry?
Identifying Basalt Porphyry – YouTube
How is porphyry deposits formed?
Porphyry deposits typically form in oceanic or continental arcs above subduction zones (Fig. 1). As the oceanic plate and overlying sediment subduct, increasing pressures expel water from the sediment, and hydrous minerals in the oceanic plate start to break down.
Where are porphyry deposits found?
What does porphyry look like?
The larger crystals are called phenocrysts. In its non-geologic, traditional use, the term porphyry refers to the purple-red form of this stone, valued for its appearance.
What minerals are found in porphyry?
In porphyry mineralization, there are many economic minerals that can be found: copper, gold, molybdenum, silver, lead, zinc, tin, and tungsten. There are also associated mineral deposits that can form that depend on the host rock and the distance from the heat source.
Is porphyry A rare stone?
Porphyry is a rare hard, purple-red stone that was highly prized in antiquity for its distinct color. Because purple was considered the imperial color, porphyry was regarded as a royal stone.
What is the difference between a porphyry and a granite?
Porphyritic granite has the same chemistry & mineralogy as ordinary granite, but differs in the size range of its crystals. Granites are coarsely crystalline igneous rocks, having a phaneritic texture. Porphyritic granites have a mix of large & small crystals, but all crystals are still fairly decent-sized.
What kind of stone is porphyry?
igneous rock
Porphyry (/ˈpɔːrfəri/ POR-fə-ree) is a textural term for an igneous rock consisting of coarse-grained crystals such as feldspar or quartz dispersed in a fine-grained silicate-rich, generally aphanitic matrix or groundmass. The larger crystals are called phenocrysts.
Is porphyry a crystal?
Porphyry (/ˈpɔːrfəri/ POR-fə-ree) is a textural term for an igneous rock consisting of coarse-grained crystals such as feldspar or quartz dispersed in a fine-grained silicate-rich, generally aphanitic matrix or groundmass. The larger crystals are called phenocrysts.