GOLD MINING IN VICTORIA.

Evening Star, Issue 4063, 4 March 1876, Page 1 (Supplement)

GOLD MINING IN VICTORIA.

The discovery of gold in a quartz lode at the depth of 1,000 feet in the claim of the Clunes Company, Climes, adds another important fact to the many already accumulated as to the distribution of gold in quartz. Year by year proofs jjre being got together that therfe is no absolute connection between the depth of a lode and its auriferous character, and, as far as our experience yet goes, we can but say that the gold varies in quantity without any relation to the depth at which it is found. At Sandhurst and Pleasant Creek like results are being reached. Whether the Magdala Company’s mine will be a profitable venture or not, we cannot, of course, say, but there is no doubt that gold has been found at the greatest depth yet reached in the Colony, and there is no known reason why it should not be in remunerative quantities there as elsewhere, At Sandhurst the Victoria Mining Company have a shaft about 1,016 ft. in depth and appearances are reported to be so favorable as to warrant the belief that the deep lodes wifi be found to pay. Other companies on the Garden Gully line have got rich quartz at considerable depths, so that it <nay be fairly said that during the year deep quartz mining has made very satisfactory progress. Time' is, of course, required to test- the true value of the discoveries made, but there does not appear to be any, reason to- doubt that 'the prospects of permanent work on our quartz lodes at considerable depths are highly encouraging. There is, so far, absolutely no evidence to show that the quantity of gold bears an inverse ratio to the depth. There is not a progressive decline in the yield. In the Clunes" Company’s claim the quartz at the greatest depth reached is reported to he richer than much found at a higher level, and no one need be surprised to hear some day that very rich stone has been opened up at a great depth as well as near the surface.

When all the ascertained facts in regard to quartz-mining are putdfcogether, it will be found, we think, that after a certain depth —that is, when a depth is reached at which the quartz is practically intact, unaffected by climate and water—the yield of gold is, so to speak, a constant quantity without relation to depth. Rich stone may be digcovered, and that may be followed by poor stone. The gold may be found to run in bands or shoots, but these will occur at all depths, and be of a similar character, on the whole, at each. Many persons, and with a good show of reason too, hold that the richness of the caps of reefs, so* often pointed out as a most important fact in connection with the distribution of gold in quartz, is due to the decomposition, through long ages, of the ore. Thus, a body of quartz exposed to heat and cold, to sunshine and rain, gradually wastes away, and is carried from the hills down to the valleys, whilst the gold remains in situ, or sinks by the force of water, through the crevices in the body of the lode. Obviously, if such a process was continued through a long series of ages, the result would be a great apparent richness at the cap of the lode, and for some short distance below. The quartz would have been, in fact, crushed by the forces of nature, • and the gold concentrated, and thus the top of the lode would, as a matter of course, seem to containa very much largerpercentage of the'' metal. There is, indeed, a great deal of evidence to show that this is the process which has been going on, and that the yiohnwe of so many caps or lodeh proves

no moro than that they have been exposed to a process of natural selection, which has carried away the quartz and left the gold behind, to puzzle and mislead a number of geological observers. If this theory be supported by the ‘ observed fapts, and we believe that it is, then the great stress laid upon the richness of the tops or caps of lodes is a grand mistake, as nothing more is proved than a long process of dennudation, because the observed richness, which is not uniform though frequent, does not indicate the natural or original condition of the quartz. It has nothing whatever to do with the primary deposit of the gold, however it was made, and is, therefore, no indication of the probable distribution of the metal at considerable depths beneath the surface of the land.

There is, in truth, no - very great degree of difference in the auriferous runs in quartz veins or lodes in any part of the world. The deposits, if they are deposits, appear to have been made under like conditions everywhere, as far as we know at the present time, and to follow some common law. There is nothing even to show that the abandoned lodes in America differ greatly from those in Australia, and the abandonment, we need scarcely tell a mining community, is no proof that there is not still gold at deeper levels in the mines. Upon this point we have the evidence of Mr Thomas Belt, F. G. S„ a gentle-: man who has written several books ■ upon mining and other subjects, and who has had mining experience in Australia, N ovia Scotia, Russia, Central America, and other places. After a careful consideration of the whole question, he comes to the same conclusion as we have expressed many times, and which increased experience shows to he the right one. Air Belt says:—“ Gold is distributed in quartz veins in bands, and patches of richer stone of more or less ex-' tent. , The richer portion of the lodes, if sunk upon perpendicularly, will be passed through, but also they would be if followed horizontally, as their extent in one direction will be as great os it is in another. The chances of meeting with further patches of rich ore in depth after one has been passed through, are about the same as in driving horizontally, and the frequency, therefore, with which the auriferous ores are met with along the surface will, as a rule, be an index of their occurrence in depth, if we be careful in distinguishing deposits belonging to the original condition of the lodes, and those due to subsequent concentration. To do this we must get below the immediate surface, and take as our guide the gold occurring in the solid quartz, and not the loose grain contained in the fissures and cavities.” This is, to a considerable extent, a precise statement of the results of our experience in thitf Colony, and the recent discoveries go to confirm the conclusion, that tfie deposits of gold at some depth below the surface follow a law, whatever it may be, which has no relation to the depth at which the gold is found.—Melbourne ‘Argus.’