. The Canadian record of science. Natural history; Science. Some Ores mid Bocks of Southern Slocan. 297. commonly found again by following the rule of normal faulting. The broken off, or rather the abrupt endings of the quartz veins, have a smooth and rounded appearance, which is hardly warranted by the slight throw, and, moreover, the vein when found again does not always correspond in thickness to where last seen. Fissure 1 illus- trates this fault- ing. It repre- sents an actual section, as seen in a prospect shaft. A curious feature of these veins is the gen- eral tendency to pitch in towa
. The Canadian record of science. Natural history; Science. Some Ores mid Bocks of Southern Slocan. 297. commonly found again by following the rule of normal faulting. The broken off, or rather the abrupt endings of the quartz veins, have a smooth and rounded appearance, which is hardly warranted by the slight throw, and, moreover, the vein when found again does not always correspond in thickness to where last seen. Fissure 1 illus- trates this fault- ing. It repre- sents an actual section, as seen in a prospect shaft. A curious feature of these veins is the gen- eral tendency to pitch in towards the centre of any given mountain, ridge or range from all sides of that mountain. Possibly this may be only a result of easier discovery of veins so situated, and there may be other ones dipping outwards with the mountain slopes, as, indeed, they do in a few cases. There is no general direction for these veins, this being a distinction from the silver lead veins, immediately north of this district, which have some tendency toward a north- easterly strike. Generally speaking, the veins are free from the granite walls and have more or less selvage matter along these walls, but it is not uncommon to find the decomposed granite and quartz firmly " frozen" or cemented together even on walls which, in other places, are quite free along the vein. Figure 2 illustrates the sudden pinching out of a quartz vein. The quartz, which carries a high value in gold, suddenly rounds off like a boulder, and only a seam of selvage matter is left, whilst on either side of the seam. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Natural History Society of Montreal. Montreal : Natural History Society
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