Transactions . lVM quartz \^rr\ SCHIST C\VlcLAY i Co., S. T. NATIVE GOLD CROSS SEAM OCCURRENCE OF A POCKET. separate mortar, and employed solely for the treatment of speci-men-ore. These rich patches occur at the places where the reefs or lodes cross bands of flinty quartz. The latter areknown among the miners as flinties. They vary in thick- THE FORM moN OF m»N VNZ IS IN GOLIM BINS. •J 17 Q688 from ;i few inches to mere threads of chalcedonic are barren in themselves, but have a favorable effect onthe gold-veins. The latter are also intersected by cross-veins,prod
Transactions . lVM quartz \^rr\ SCHIST C\VlcLAY i Co., S. T. NATIVE GOLD CROSS SEAM OCCURRENCE OF A POCKET. separate mortar, and employed solely for the treatment of speci-men-ore. These rich patches occur at the places where the reefs or lodes cross bands of flinty quartz. The latter areknown among the miners as flinties. They vary in thick- THE FORM moN OF m»N VNZ IS IN GOLIM BINS. •J 17 Q688 from ;i few inches to mere threads of chalcedonic are barren in themselves, but have a favorable effect onthe gold-veins. The latter are also intersected by cross-veins,producing an enrichment similar to that caused by the Fig, 3 is a sketch of one of these intersections, as seenby me in the Moanataeri mine. The lode, A It. consists ofa Beries of small Beams of quartz, conforming to 111«- struc- Fia. ,! .v. r. ENRICHMENT AT INTERSECTION MOANATAERI MTNE, NEW ZEALAND. tnral lines of the enclosing country, which is hornblende-ande-site. The cross-vein, CD, is a band of soft gray decomposedrock, which also carries a number of small quartz-seams, butonly near its crossing with the main lode, AB. The lineof CD is parallel to a large fault, to be seen elsewhere in themine-workings. The leaders, or quartz-seams, in AB aregold-bearing, and exhibit marked enrichment at the intersec-tion with CD. 218 THE FORMATION OF BONANZAS IN GOLD-VEINS. The prevailing formation of this mining district is an ande-site, which is traversed by soft bands of decomposition, called sandstone hy the miners. The latter, when penetrated byquartz-seams, are favorable to the finding of ore. The gold-pecurrence is essentially sporadic and dependent upon local en-richments, such as have been described. The district is sur-rounded by thermal springs, and is near the well-known volcanicregion of Tarawera, which
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Keywords: ., bo, bookcentury1800, bookdecade1870, booksubjectmineralindustries
