Alluvial gold

“ The ordinary non-scientific digger will do well to give credence to this view of the case, and will often thereby save himself much useless trouble. Sometimes also the alluvial gold, coarser in size than true reef-born alluvial, is derived almost in situ from small quartz "leaders," or veins, which the grinding down of the face of the slates has exposed; these leaders in time being also broken and worn, set free the gold they have contained, which does not, as a rule, travel far, but sometimes becomes water-worn by the rubbing over it of the disintegrated fragments of rock. ”

“ It is then hauled up to the surface, and once a week the dirt is washed, being passed through wooden channels; the gold, being heavier than the stones and gravel, sinks to the bottom of the channel, and is caught by rough battens; the extreme end of the channel covered with a piece of plush retains the very fine gold brought down by the rush of water. From all I can gather, gold costs a considerable percentage of its value, but it has the advantage of being always saleable at a fixed price. Alluvial gold is got with much greater ease than gold in quartz, and is much more profitable. ”

“ Rich as the auriferous drifts of the deep alluvial deposits are frequently found to be, they must be within definite limits, having been deposited by currents and the continuous action of waves not far from the localities where the gold was originally formed. But the alluvial gold of Victoria and New South Wales is not confined to drifts and gutters. There are hundreds, probably thousands, of square miles, where the clay, earth, and sand are impregnated with gold in sufficient quantities to pay well for washing. ”

“ We know, too, that the real extent of the gold region is hitherto the object of speculation and hope, rather than actual survey or knowledge. It is quite probable, too, that our calculation, which is a mere rough guess, may be above the mark in some particulars, and below it in others. Still, enough, making allowance for all such errors, remains to show that, in the alluvial gold region alone, if the accounts of its extent and riches are at all to be relied on, there is ample room for a vast annual addition to the treasures of the earth for a great many generations to come. ”

“ Nuggets, properly so-called, are never found in quartz lodes; but, as will be shown later, a true nugget having all the characteristics of so-called waterworn alluvial may be artificially formed on a small piece of galena, or pyrites, by suspending the base metal in the loop of a thread in a weak solution of chloride of gold in which a few hard-wood chips are thrown.
Prospecting for alluvial gold at shallow depths is a comparatively easy process, requiring no great amount of technical knowledge. Usually the first gold is got at or near the surface and then traced to deep leads, if such exist. ”

“ The Botanical Gardens are always beautiful, and are a model to other establishments of the same kind in much larger communities.'
It was here, early in August 1851, that alluvial gold was discovered at a bend in the Yarrowee Creek, renamed Golden Point, where the toil of some of the earlier diggings yielded from twenty to fifty pounds weight of gold per day. In some spots, indeed, the gold lay almost on the surface, amidst the roots of the bush grass, to be turned up by the wheels of the passing bullock-drays, or picked out by hand after heavy showers. ”

“ Assuming that alluvial gold is in the main a derivative from reef gold, it is certainly strange that streams flowing in well-nigh opposite directions, and yet rising within very short distances of one another, should be so largely charged with gold, unless they have obtained it from a common source ”

“ Getting gold practically means, in modern times, crushing stone. This statement is subject to fewer and fewer exceptions from one decade to another, according as the alluvial deposits in the various gold-producing countries become more or less completely worked out. A partial revival of alluvial mining has been brought about through the application of the giant dredger to cheapening the process of extracting exceedingly small quantities of gold from alluvial drift and dirt. ”

“ And, lastly, why is it that when an alluvial lead is traced up to, or down from, an auriferous reef, that the light, angular gold lies close to the reef, while the heavy masses are often bedded much farther away? Any one who has worked a ground sluice knows how extremely difficult it is with a strong head of water to shift from its position an ounce of solid gold. What, then, would be the fluvial force required to move the Welcome Nugget? ”

“ Having considered the origin of auriferous lodes, and the mode by which in all probability the gold was conveyed to them and deposited as a metal, it is necessary also to inquire into the derivation of the gold of our auriferous drifts, and the reasons for its occurrence therein.
When quite a lad on the Victorian alluvial fields, I frequently heard old diggers assert that gold grew in the drifts where found. ”

“ In many sections gold is known to exist in abundance and with further exploration it will doubtless be discovered in others. It is found in alluvial deposits, also in veins or lodes of quartz, from which the deposits are the washings. Veins of antimony which are common in Bolivia contain gold in chemical or mechanical mixture. ”

“ The sands of some of the rivers from which portions of the gold supply of the old world was derived are still washed over year after year in exactly the same manner as was employed, probably, thousands of years ago, the labour, very arduous, being often carried on by women, who, standing knee deep in water, pan off the sand in wooden bowls much as the digger in modern alluvial fields does with his tin dish. ”

“ Gold is found in tolerable quantities, even by the Malay easy-going manner of searching for it, and diamonds and garnets are tolerably abundant. Gold can be washed with little difficulty from most of the river beds, and from various alluvial deposits. The metal thus found is pure, but "rough and shotty." The nearer the mountains the larger the find. ”

“ Gold differs in its mode of occurrence from other metals in many respects; but there is no doubt that it was once held in aqueous solution and deposited in its metallic form by electro-chemical action. It is true we do not find oxides, carbonates, or bromides of gold in Nature, nor can we feel quite sure that gold now exists naturally as a sulphide, chloride, or silicate, though the presumption is strongly that it does. If so, the deposition of the gold may be ceaselessly progressing.
Generally reef gold is finer as to size of the particles, and, as a rule, inferior in quality to alluvial. ”

“ The gold lies in quartz veins which traverse a very crumbling reddish granite.
Africa was, with Spain, the source of the greater portion of the gold possessed by the antients. The gold which Africa still brings into the market in abundance is always in dust, showing that the metal is obtained by washing the alluvial soils. ”

“ Gold is found almost invariably in the metallic state. It occurs as gold dust in the sands of various rivers, and in the alluvial soil of auriferous districts, from both of which it is obtained by the simple process of washing. Traces of it are constantly found in the iron and other pyrites of the more ancient rocks. Sometimes it occurs beautifully crystallised in the cubic form, associated with quartz, oxide of iron, and other substances, in regular veins. In the gold fields of California and Australia lumps of nearly pure gold have been discovered in abundance during the last few years. ”

“ The gold first worked for in Australia, as in other places, was of course alluvial, by which is usually understood loose gold in nuggets, specks, and dust, lying in drifts which were once the beds of long extinct streams and rivers, or possibly the moraines of glaciers, as in New Zealand. ”

“ The preceding notes show that the natives of the Gold Coast, and of West Africa generally, are adepts at procuring their gold by 'surfacing,' washing with the calabash or wooden bowl the rich alluvial formations that underlie the top-soil. This is the rudest form of machinery, preceding in California the cradle, the torn, and the sluice. Westerns made their pans of brass or copper, about sixteen inches in diameter, and nearly two inches deep in the middle where the gold gravitates. Panning in Africa is women's work, and the process has been described in the preceding pages. ”

“ Of course in large alluvial claims, where capital is employed, such appliances are superseded by steam puddles, buddles, and other machinery, and sometimes mercury is used to amalgamate the gold when very fine. Hydraulicing is the cheapest form of alluvial mining, but can only be profitably carried out where extensive drifts, which can be worked as quarry faces, and unlimited water exist in the same neighbourhood. When such conditions obtain a few grains of gold to the yard or ton will pay handsomely. ”

“ Gold and other minerals are found, the gold in quartz and alluvial, and if properly prospected would, from ill information obtained, become a most valuable gold-field; besides the copper and silver that are known to exist in great quantities along the spurs of the mountain. ”

“ Hence the alluvial territories have always been the chief sources of auriferous wealth, and this circumstance explains how countries which at one time abounded in gold have long since ceased to be of importance. ”

“ Ferdinand Fitzgerald, of the famous 'African Times.' When its directors inform us that 'twenty ounces of gold lately arrived from a neighbouring mine, the produce of stamping of twenty-five tons of ore, similar to that of Tamsoo-Mewoosoo,' they may not have been aware that the produce in question was worked from the alluvial drift discovered, about the end May 1881, in the north-western corner of the Swanzy estates. ”

“ About two-thirds of our gold is obtained from the placers, and one-third from the quartz.
A mine is defined and generally understood to mean "a subterraneous work or excavation for obtaining metals, metallic ores or mineral substances;" but this definition does not apply to our placer mines, which are places where gold is taken from diluvial or alluvial deposits. Most of the work is not subterraneous; it is done in the full light of day. ”

“ The digger of to-day having discovered payable alluvial dirt at such a depth as to permit of its being profitably worked by small parties of men with limited or no capital, procures first a half hogshead for a puddling tub, a “cradle,” or “long tom,” and tin dish. The “wash dirt,” as the auriferous drift is usually termed, contains a considerable admixture of clay of a more or less tenacious character, and the bulk of this has to be puddled and so disintegrated before the actual separation of the gold is attempted in the cradle or dish. ”

“ The recesses of the mountains and the rivulets that derive their sources from them are said to be rich in gold and silver, and they are also reported to yield copper and iron; it is, however, with great difficulty that gold is procured, on account of a superstitious feeling on the part of the mountaineers, who think it necessary to sacrifice a human life for every bottle of gold dust that is collected ”

“ After heavy showers the naked eye can note spangles of the precious metal in the street-roads. You can pan it out of the wall-swish. The little stream-beds, bone-dry throughout the hot season, roll down, during the rains, a quantity of dark arenaceous matter, like that of Taranaki, New Zealand, and the 'black sand' of Australia, which collects near the sea in stripes and patches. The people believe that without it gold never occurs; and, if they collect the common yellow sand, it is to extract from it the darker material. ”

“ Throughout this whole region there is not a stream, valley, hill, or plain, in which gold does not exist. It seems to be the natural product of the soil, and is borne like the sand along the river courses. In travelling over some three hundred miles of this territory, I have never yet struck a pick or a knife into any spot where gold would be likely to be deposited, without finding it in greater or less quantities. ”

“ The gold deposits are found in the quartz and slate formations, in decomposed granite, in sand and gravel beds, and in clay. The largest specimens are found between the layers of slate over which the stream flows vertically. The rocks and soil are frequently volcanic, like those of Pompeii. Lumps of gold are often found alone, and are no indication of the existence of a rich deposit. But the scale and dust gold is not found in this detached state; it exists generally in veins, though sometimes much scattered through the soil by the action of the water. ”

“ Hence it was long and erroneously determined that bare rocks in the neighbourhood of shallow alluvia characterise rich placers, and that the wealthiest mining-regions are poor and stunted in vegetation. California and Australia, the Gold Coast and South Africa, are instances of the contrary. Wásá, however, confirms the old opinion that the strata traversed by lodes determine the predominating metal; as quartz produces gold ”

“ I have found, in the dry diggings of Weaver’s Creek, pieces of gold, some of them weighing nearly a quarter of an ounce, lying in the upper black soil within two inches of the surface. It is sometimes found embedded in a hard white clay, at other times in a red, and at others in a blue clay. As a general thing, I have found that where the gold is coarse, it usually descends until it reaches one of the above-mentioned clays, while the finer particles rest upon the gravelly stratum nearer the surface, and thus fine gold is most frequently found mingled with red gravel. ”