Granite range

The hard rock deposits are mined mainly for feldspar with mica and quartz being accessory minerals. These deposits are extensive, often covering hundreds of square meters and are recognized by the light-colored, granite-like appearance with shiny mica flakes being a prominent feature. The mica content of these deposits ranges from approximately 6—10 wt %. 

In vertisols on diorite, basalt, alluvions, and dolerite, total Mn is in the range of 1250-2750 mg/kg, while brown isohumic soils on calcareous sandstone and clayey sediments contain 550-1670 mg/kg Mn. Soils in the Adelaide and Southeast regions contain 140-1400 mg/kg total Mn. In solods on granitic rocks and alluvions, total Mn is 60-990 mg/kg. 

Determine the range of velocities over which a bed of granite particles (SG = 4) would be fluidized using... 

The Archaean Yilgarn Craton is composed mainly of granite, with mafic, volcanic and sedimentary greenstone rocks. It is one of the world s principal mineral provinces, with considerable resources of primary and supergene Au, sulfide-hosted and lateritic nickel, bauxite, as well as a wide range of other commodities. 

Ores of magnetic origin. Tantalum/columbite granites are of economic interest when the columbite content of the ore ranges from 0.001% to 0.01% and the tantalite up to 0.2%. These deposits are most common in Nigeria (Africa). Because they are a low-grade ore, they do not represent significant economic value. 

Subsequent studies with improved analytical techniques include data from granitic rocks reveal values ranging from 15%o lighter than MORE to 20%o heavier. A number of granitic... 

Figure 11.23 shows the isochron obtained by Marshall and De Paolo (1982) for the granite batholith of Pikes Peak (Colorado). The effectiveness of the double-spike technique is evident, especially when we see that aliquot-spiked samples do not fall on the best-fit interpolant (York s algorithm York, 1969). The obtained age (1041 32 Ma) is consistent with that previously obtained with Rb-Sr whole rock analyses (1008 13 Ma see Marshall and De Paolo, 1982, for references). The initial ratio ( Ca/ Ca)o of 151.0 is identical, within the range of uncertainty, to upper mantle values, indicating negligible contamination by old crust components the relative K/Ca abundance in the earth s mantle is about 0.01, a value too low to alter the primordial (" Ca/" Ca)o composition. 

The layered quartzite occurs as xenoliths in the granite. The contact between the two units is sharp and discordant, and is locally undulatory. The xenoliths have rounded edges and range in size xenoliths are very rare within the Main Double S Zone and do not contain U mineralization (e.g., 250-300 c/s). 

McNeal, J.M., Lee, D.E., Millard, Jr. FI.T. 1981. The distribution of uranium and thorium in granitic rocks of the basin and range province. Western United States. Journal of Geochemical Exploration, 14, 25-40. 

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