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The San Juan formation contains the majority of the ore bearing veins that will be mined at <br />Revenue. The majority of rocks in the San Juan Formation are fine grained andesite, which is made <br />up primarily of quartz, amphiboles amphiboles, feldspar, biotite and muscovite mica. The andesite is <br />described according to the Geology of the Revenue Area: <br />Within the mine workings it is recognized by its maroon to lavender color, <br />abundance of large breccia clasts, and its tendency to fracture parallel to the <br />workings, forming slabs and "scales on the ribs and back of the tunnels. Above <br />ground it forms steep rounded slopes and cliffs and ranges from 2000 to 2600 ft. <br />This andesite makes up the bulk of the waste rock that was mined from the revenue Tunnel and is <br />the rock which exists in the current Revenue waste rock pile shown on Map C -1. Numerous dikes, <br />mostly trending northwest, are to be found throughout the local geology. <br />These dikes form a close relationship with the fissure vein mineralization relevant to the Revenue <br />Mine. These dikes dip generally greater than 65 degrees, and can be anywhere from 2 to 20 feet <br />thick. These dikes make up most of the footwall and highwall within the existing and likely future <br />drifts. The Virginius Vein in particular is partially hosted by aphanitic to sparsely porphyritic <br />andesite dikes. <br />The fissure veins consist of the following minerals of interest in a quartz host rock: <br />- galena (PbS) <br />- sphalerite (ZnS) <br />- chalcopyrite (CuFeS2) <br />- Tetrahedrite (Cu12Sb4S13) with a variant freibergite which has some silver (Ag) replacing some of <br />the copper. <br />It is expected that these minerals will comprise approximately 20 -40% of the vein material. The <br />remaining minerals are inert host materials (such as quartz). The veins range in true width of 1 -4 <br />feet. <br />Revenue Mine August 2012 i -8 <br />