A Study of the Visible Indications of Ore Value in the Metadiorite of the Mother Lode Area Near Jackson, California ... |
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Page 26
... polished sections of typical portions . The photographs of the specimens in their natural form were taken with a Zeiss Contessa Nettal camera with a 16.5 centi- meter , f 2.7 lens and a focal plane shutter . A bellows exten- sion was ...
... polished sections of typical portions . The photographs of the specimens in their natural form were taken with a Zeiss Contessa Nettal camera with a 16.5 centi- meter , f 2.7 lens and a focal plane shutter . A bellows exten- sion was ...
Page 27
... sections were further ground The pictures of the polished sections were taken with a large Bausch and Lomb metallograph , with the aid of a macro- scopic attachment . These photographs were magnified five times . Four - by - five - inch ...
... sections were further ground The pictures of the polished sections were taken with a large Bausch and Lomb metallograph , with the aid of a macro- scopic attachment . These photographs were magnified five times . Four - by - five - inch ...
Page 28
... polished sections . The estimation of th percentage of pyrite in the specimens was done in part from the microscopic study of the polished sections , and in part from an examina- tion of the rough specimens . The calculated value of the ...
... polished sections . The estimation of th percentage of pyrite in the specimens was done in part from the microscopic study of the polished sections , and in part from an examina- tion of the rough specimens . The calculated value of the ...
Contents
Factors Contributing to This Study | 23 |
Inaccuracies in Study | 28 |
Negative Results of Study | 31 |
2 other sections not shown
Common terms and phrases
420 drift Distance 420 drift Position 450 Distance 65 degrees 7x natural 7x natural size abundant altered to talc assay Au per ton bands Calcite Calculated pyrite value Central belt chalcopyrite constituent of specimen country rock cross-faults crystalline crystallized pyrite crystals see Plate degree of crystallization diorite Distance above level East belt east-west vein Easyz Bird vein estimated degree euhedral fissures foot-wall side Fracturing free gold Fyrite geology gold content Gold Deposits gold value gouge hanging-wall side highly altered impregnation inches irregular and massive Lovel Magnification massive and irregular massive bull massive pyrite mesothermal meta metadiorite area mineral MOKELUMNE HILL north-south vein system numbers perfect cubical crystals polished sections Position in vein precipitation present principal constituent PY Qtz pyrite crystals pyrite cubes Pyrite percentage Q+z Py raise Distance region Replacement slightly fractured small amount small irregular masses speci tion transparent Valuc vugs wall-rock walls