Transactions . 15gold-masses or nuggets found as above described, and varyingin weight from 30 to 137 ounces, and in depth from the surface(measured on the indicator) from 160 to 805 feet, the averagebeing 470 feet. In the same report he raises several questionsas to the source and distribution of the gold in the indicators,and says that the solution of these problems will require aseries of investigations of the country-rock, like those performedby Sandberger in Germany. The Prince Regent Mine.—Before seeing Mr. Lidgeys reportI had taken a set of samples for the purpose suggested, select-ing
Transactions . 15gold-masses or nuggets found as above described, and varyingin weight from 30 to 137 ounces, and in depth from the surface(measured on the indicator) from 160 to 805 feet, the averagebeing 470 feet. In the same report he raises several questionsas to the source and distribution of the gold in the indicators,and says that the solution of these problems will require aseries of investigations of the country-rock, like those performedby Sandberger in Germany. The Prince Regent Mine.—Before seeing Mr. Lidgeys reportI had taken a set of samples for the purpose suggested, select-ing the Prince Regent mine, one of the most productive on theindicator belt, as likely to be most instructive from a geneticstandpoint, because it had shown, as the depth of the mine in-creased, a marked change in the auriferous contents of the 570 THE GENESIS OF CERTAIN AURIFEROUS LODES. veins crossing the indicators. This mine is about 870 feetdeep. Down to the 630-foot level, pay-quartz, sometimes with Fig. Slaty Sandstone Quartz The Indicator VERTICAL SECTION OF THE INDICATOn, BALLARAT-EAST. Showing quartz veins.(After T. A. Rickard.) rich patches, was worked on the main indicator and on parallelones; but for the last 240 feet the former has been barren and THE GENESIS OF CERTAIN AURIFEROUS LODES. 571 the latter have been much less productive than before. Sam-ples were therefore taken on the 630-foot level, where the indi-cator had carried pay-quartz, and from the 770-foot level,where it had proved almost barren. The ground near the indicators has been much faulted; andthis faulting was found to have an interesting connection withthe genesis of the auriferous deposits. The questions raised byMr. Lidgey comprised, besides the general inquiries,—Was thegold on the indicators leached from the surrounding country -rock? Was it brought from below by ascending, or fromabove by descending, solutions ?—the more specific ones, Whyis the gold on these indicators concentrated in
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Keywords: ., bo, bookcentury1800, bookdecade1870, booksubjectmineralindustries
