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�00 <br /> "TWINING <br /> CONCRETE INSIGHT <br /> Morrison Quarry Rock Petrography Page 54 <br /> 4.8 Rock Sample HDR-005 (115.0-115.7): Chlorite-Biotite Gneiss <br /> Received Condition <br /> The sample is a cored rock fragment that measures —60 mm (2 % in.) in diameter and <br /> —190-213 mm (7 '/2 - 8 % in.) in length (Figure 4.8a). Both ends of the core are fractured <br /> surfaces and the side surfaces are rough cored surfaces. The core was received intact in one <br /> piece. No weathered surfaces are present. <br /> Polished Slab <br /> The rock on the polished surface is pale pink and bluish-gray to bluish-black (Munsell Soil <br /> Color 2.5YR 5-6/2 and GLEY 2 2.5-4/5PB) and predominantly consists of quartz, orthoclase <br /> feldspar, plagioclase feldspar, biotite, and chlorite, with trace amounts of opaque minerals <br /> (Figure 4.8b, Figure 4.8c). The rock sample exhibits a moderate to well developed gneissose <br /> structure with alternating felsic (quartz, feldspar) and darker mineral layers (biotite, chlorite). <br /> Gneissic layers measure up to —4 mm ('/8 in.) thick and are laterally continuous. Quartz and <br /> feldspar grains are medium grained and measure up to —2 mm (80 mil) in diameter. The rock <br /> sample exhibits a few randomly oriented quartz-rich veins. The sample is hard and <br /> competent, and exhibits a mohs hardness of 3-4+. <br /> Thin Section <br /> The rock is a high-grade metamorphic rock classified as a chlorite-biotite gneiss <br /> (Figure 4.8d, Figure 4.8e, 4.8f). The sample consists of major amounts (>10%) of medium <br /> grained quartz, orthoclase feldspar, plagioclase feldspar, biotite, and chlorite measuring up to <br /> —2 mm (80 mil) in diameter. A trace amount (<1%) of opaque minerals are observed. Quartz <br /> and felspar grains are subhedral to anhedral in shape and occur as segregated layers. Quartz <br /> occasionally occurs in veins throughout the sample. Biotite and chlorite grains are elongated <br /> in shape and exhibit a preferred orientation. <br /> s <br /> Major minerals Quartz(-40-50%),felspar(-20-30%),biotite(-10-20%),chlorite(-10-20%) <br /> (10-100%by volume of rock) <br /> Minor minerals N/A <br /> (1-10%by volume of rock) <br /> Trace minerals Opaque minerals <br /> (<1/o by volume of rock) <br /> Report No. 227893.d 22 November 2022 <br />