There is an old proverb or miner´s slogan: "Gold is where you find it" the current list shows you wherever you can find gold at an economic grade
1)Magmatic gold deposits
1)Volcanicmassive sulfide deposits (VMS)
(1)Kuroko-type
(2)Besshi-type and Ural-type
(3)Cyprus-type
(4)Iberian-type
(5)Greenstone-Belt-type
(6)VMS deposits of unknown type in medium to high grade metamorphic terrains
2)Listwanite-type Au deposits related to ultramafic igneous rocks
3)Gold deposits associated with felsic intrusions—igneous rocks (IRG-systems)
4)Porphyry Cu-Mo-Au deposits including co-magmaticbreccia pipes
(1)Calcalkaline porphyry Cu-Au-Mo deposits and Cu-(Mo) breccia pipes
(2)Alkalic porphyry Cu-Au/ diorite porphyry copper
5)Pyrometasomatic Au skarn deposits
6)Shallow high- and low-sulfidation Cu-Au-Ag deposits
1)High sulphidation-type/ quartz alunite-type Au-Ag-Cu deposits
2)Low sulphidation-type/ adularia-type Au-Ag deposits
3)Hot spring Au deposits bound to subaerial siliceous sinter
7)Mn-Au-Ag-Fe-Ba-F low-sulfidation deposits
8)Alkaline igneousrock-relatedAu-Ag-Te deposits
9)Carbonate-hosted disseminatedAu-Ag deposits(Carlin-type)
10)Cu-P-REE-U-Th-(Au –PGE) vermiculite deposits
2)Structure-related gold deposits
1)Orogenic gold deposits
2)Iron oxide breccias with Cu-Au-Ag-U deposits
3)Sedimentary gold deposits
1)Laterite-saproliteAu-(PGE-Sn)-Fe-Al-Mn deposits
2)Au-PGE placer deposits
3)Buried (Paleo) Au-U-(PGE-Th) placers (quartz pebble conglomerate) (
4)Au-bearing banded iron formation
5)Au-bearing black shales
6)Au-bearing coal
4)Metamorphic gold deposits
1) Metamorphic Au-As-Pd-Hg-Bi-Te mobilizates
For further reading see "The chessboard classification scheme... by the poster
HGD
The legendary # 4 porphyry deposit at the Barnat mine of the Abitibi greenstone belt, Quebec was probably the ideal gold deposit in that area. Most geologists who worked in the Abitibi in the 1970's were striving to understand how it formed and how could someone find a similar deposit.
The # 4 porphyry deposit formed entirely within a porphyritic intrusion (extrusion) and was located in a sequence of altered ultramafic lavas (komatiites). The porphyry had a stockwork of veins mineralized with quartz and pyrite. There is no detailed description of the geology of the deposit, but it contained probably a million tons of about 6 grams per ton.
Many other porphyry deposits were mined at the same mine, but were of much lower grade and tonnage.
It is thought that the komatiites were the source of the gold. The intrusions and their hydrothermal solutions leached the gold and deposited it within the cooling magma.
The accompanied map after Fallara, 2000 shows the location of the porphyry between two major regional faults that are thought to have concentrated several gold deposits in the area.
Large deposits are usually polygenic and polychronous. A number of processes are involved in their formation, including superimposed ones.
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