Content Silica Resources Quartz types Quartz specifications for high technical applications Classification of the quartz quality Quartz Deposits in Egypt Marwit Rod El Leqah Field study Petrography Geochemistry Economic Aspects Conclusion

Silica is the name given to a group of minerals composed of silicon and oxygen (SiO 2 ), found in both crystalline state and amorphous state. Silica represent 12.6 weight% of the Earth’s crust

Chalcedony Rose QuartzBlue quartzz Smoky Quartz Citrine Carneline Rock crystalAmethyst

Ezzeldin et al, (2007) Harben ʾs classification (2002) The price of low quality quartz from 15 to 20 dollars per ton while the price of high purity quartz is 2000 dollar per ton or more according to the product type. SiO 2 %Type Not less than 99.9 High purity quartz 99.5≤Very pure quartz 99 to 99.5Pure quartz 98 to 99Less pure quartz Less than 98Un pure quartz

S.NoR1R2R3R4R5R6 SiO TiO 2 < 0.01 Al 2 O Fe 2 O MnO< 0.01 MgO< 0.01 CaO< 0.01 Na 2 O< 0.01 K2OK2O P2O5P2O L.O.I Trace elements (ppm) V< 1 Cr Co Ni Cu Zn Ga< 1 As< 1 Sr< 1 Zr Mo2< Sn Sb Ba< 1 La< 1 Hf< 1 Pb Th U324343

Chemical analyses of crude Marwit Rod El Leqah quartz samples showed to match the specifications of many advanced applications like aluminum alloys (98% SiO 2, 0.02% Fe 2 O 3, 0.3% CaO and 400 ppm Ti), ferrosilicon alloys (98% SiO 2, 0.4 % A1 2 O 3, 0.2 %, each of Fe 2 O 3, CaO, and MgO), silicon carbide (99.50 to % SiO 2, 0.04 to 0.05 % Al 2 O 3, 0.05 to 0.1 % Fe 2 O 3 and 1.10 % CaO + MgO), and electrode industry (97.5 to 99.5 % SiO 2, 0.05 % Fe 2 O 3 and 0.03 % (max.)S. Yet, these chemical specifications do not match the requirements of high technical applications like silicon metal (99.67% SiO 2, 0.08% Al 2 O 3 ), silicon for solar cells (> 99.8% SiO 2 ), electronics (99.8% SiO 2, 0.05% Al 2 O 3 ) and optical applications ( SiO 2 %, Fe 2 O 3 ≤ %, A1 2 O 3 ≤ 0.075%).

The relative low SiO 2 content in Marwit Rod El Leqah quartz body (99.57%) was classified this deposit as medium purity quartz (with about 4250 ppm impurities). The accepted level for high purity quartz was > % SiO 2 ( with less than 50 ppm impurities). Accordingly, the quartz deposits of this area do not match the chemical requirements for the high technical applications like the production of metallurgical, solar, and electronic silicon metal.

The applying of the proper beneficiation techniques to separate and remove as possible the present solid impurities in Marwit Rod El Leqah quartz is a must to upgrade the quality of the sample to match the specifications required for high technical applications.

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