 | Royal Geological Society of Cornwall - 1871 - 794 páginas
...which is generally parallel to the cleavage of the adjoining strata. •Ante, pp. 191—4, 251. t" The enclosing rock, which within 20 feet of the surface...becomes a hard compact talcose schist, often containing " fine-garnets, and not unfrequently iron pyrites. In this schist, at a small depth, " are a multitude... | |
 | William Jory Henwood - 1871 - 766 páginas
...which is generally parallel to the cleavage of the adjoining strata. • Ante, pp. 191—4, 261. f " The enclosing rock, which within 20 feet of the surface...becomes a hard compact talcose schist, often containing ' fine-garnets, and not unfrequently iron pyrites. In this schist, at a small depth, ' are a multitude... | |
 | Royal Geological Society of Cornwall - 1871 - 776 páginas
...which is generally parallel to the cleavage of the adjoining strata. •Ante, pp. 191—4, 261. f " The enclosing rock, which within 20 feet of the surface is hardly to be 1 distinguished from the vein, gradually changes below this point, and within a 1 depth of 10 or 15... | |
 | Virginia. Division of Mineral Resources - 1913 - 736 páginas
..."vein-stone," while in structure it coincides with the neighboring rocks." According to Prof. Ansted, "the enclosing rock, which within 20 feet of the surface...depth of 10 or 15 feet becomes a hard, compact talcose [probably quartz-sericite] schist, often containing fine garnets, and not infrequently iron pyrites.... | |
 | Virginia. Division of Mineral Resources - 1913 - 816 páginas
..."vein-stone," while in structure it coincides with the neighboring rocks." According to Prof. Ansted, "the enclosing rock, which within 20 feet of the surface...depth of 10 or 15 feet becomes a hard, compact talcose [probably quartz-sericite] schist, often containing fine garnets, and not infrequently iron pyrites.... | |
 | Stephen Taber - 1913 - 872 páginas
...enclosing rock, which within 20 fei the surface is hardly to be distinguished from the vein, gradual Changes below this point, and within a depth of 10 or 15 feet becomes *Jard, compact talcose [probably quartz-sericite] schist, often containir line garnets, and not infrequently... | |
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The enclosing rock, which within 20 feet of the surface is hardly to be " distinguished from the vein, gradually changes below this point, and within a " depth of 10 or 15 feet becomes a hard compact talcose schist, often containing " fine-garnets, and... 