Porphyry molybdenum deposit, associated with a small granite porphyry stock.

One of China's largest molybdenum deposits.

The output of Mo ore in Jinduicheng Molybdenite has reached 1 million tons. It is the largest Mo mining area in China and Asia, with an average grade of 0.099%. The mining area is contained in andesite and granite porphyry. The rock contains polymetallic sulfide minerals. In addition to molybdenite, the rock also contains pyrite, chalcopyrite, limonite, hematite, etc. The U content is relatively high in granite porphyry, especially in mineralized potassium feldspar porphyry. The results of a sample analysis of the ore show that the maximum U content is about 50.94 mg/kg, and the average content is about 19.77 mg/kg.

The Jinduicheng alkaline granite porphyry in the mine area is about 400 m long and 150 m wide, with an outcrop area of 0.067 km2 ,striking N50°W. The Mo mineralization takes place at the contact of the Jinduicheng granite porphyry with the country rocks. The orebody has a tabular shape, measuring 2200 m in length, 600–800 m in width and 600– 700 m in thickness. In 1955 reserves at Jinduicheng were estimated at 978 kt of Mo metal, with an average grade of 0.099%. During the following years, this estimate has been extended by another 100 kt. The mineralization can be divided into three stages: 1) barren K-feldspar–quartz veins, 2) K-feldspar–quartz–sulfide veins and/or quartz–sulfide veins and 3) quartz–calcite–sulfide and quartz–zeolite–pyrite. Stage 2 is the most significant stage and largely responsible for the Mo mineralization. The Mo mineralization consists of a classic stockwork, accompanied by nearly pervasive alteration of K-feldspar, quartz, fluorite, and less sericite, zeolite and calcite.

Geochronology

Mineralization age: Early/Lower Cretaceous : 139.2 Ma to 129 ± 7 Ma

Important note: This table is based only on rock and mineral ages recorded on mindat.org for this locality and is not necessarily a complete representation of the geochronology, but does give an indication of possible mineralization events relevant to this locality. As more age information is added this table may expand in the future. A break in the table simply indicates a lack of data entered here, not necessarily a break in the geologic sequence. Grey background entries are from different, related, localities.

Geologic Time				Rocks, Minerals and Events
Phanerozoic
	Mesozoic
		Cretaceous
			Early/Lower Cretaceous	ⓘ Molybdenite (youngest age) 129 ± 7 Ma ⓘ Molybdenite (oldest age) 139.2 Ma

Other Regions, Features and Areas containing this locality

References