G
Guest
Alluvial Prospecting.
(BY C. B. SMTTH.)
The Immediate hope of thousands of unemployed men In this State undoubtedly lies in the winning of alluvial gold. Very little knowledge Is required to make a start, and
all the equipment that is necessary to begin with is a pick, a shovel, and a prospecting
dish Once a likely spot is found it will be necessary to construct a "cradle" or sluice box, but these can easily be made, at a cost of a few shillings. Where running water la available, hand-sluicing enables a man to put through about 10 times as much in a day as he will treat in a "cradle," and a hundred times as much as he will treat In a dish. The dish should really only be used for preliminary fossicking, to get Indications of "colour," and to wash the concentrates that collect in the riffles and cradle "apron."
Alluvial deposits are of great importance at the present moment because: (a) No capital is required beyond rail fare, a few shillings' worth of equipment, and a fortnight's rations; (b) the greater quantity of the world's gold has been won from alluvial deposits, and (c) the returns, though smaller than from reef ore, are more certain. In fact, provided two men are working In a field which has gold bearing wash dirt, a supply of water, a rude equipment, a knowledge of procedure, and the will to do at least eight hours' solid work a day, there is little doubt that they will make a living on an alluvial field. With luck it may prove a very good living, but the primary consideration at present is that the rewards should sustain them and their families in the necessities of life.
HOW TO SUCCEED.
At some time in the earth's history alluvial gold has been washed down from the parent reefs and deposited in the beds of rivers and creeks.
The prospector's first work is to carefully wash the gravels of streams to determine whether any gold Is there at all. Next, certain beaches along the course of the stream should be selected and shallow pits sunk through them until bedrock is met with, and all the material raised should be panned. Being one of the heaviest of minerals, gold will generally gravitate, In the course of time, to the very bottom of the river bed, and it is there that the heavier nuggets will frequently be found.
Follow the river or creek up the stream, especially when it is low, and clean out with a knife all likely crevices In the rocks in which gravel and sand have accumulated This should be carefully washed. in some cases large quantities of gold have been won by prospectors in a short time by prospecting in this manner.
In Western Australia and In certain dry areas of New South Wales, the rainfall is not sufficient to wash the gold for any distance from the reefs in such cases there are generally flats in which gold occurs through the surface soil for a depth of a few feet.
Surface deposits of this nature indicate that a gold-bearing reef or lode, from which they have been washed, is not very far away, and this fact gives the prospector great incentive to search for the parent reef in the immediate neighbourhood.
PERSEVERANCE ESSENTIAL.
The gold found in ordinary rivers, of course does not necessarily mean that the reef from which it came is in close proximity It may have been carried a great many miles from its original home by flood waters.
It is well to bear in mind, in searching the sand and gravel washed down by rivers, that if the bed of a river yields fine gold dust, it will probably yield larger grains of gold higher up the stream, and grains of gold will suggest nuggets nearer the source of the river. The water has simply washed the fine particles of gold a long way from its source leaving the heavier nuggets nearer the parent reef.
One cannot lay down any hard and fast rules for prospecting for the deposits buried in river beds, but a careful prospector will take particular notice of where the stream has altered its course slightly here and there leaving the sand and gravel that once formed it bed high and dry
A wise prospector, in cases such as this .will generally sink shafts through these gravels until bedrock is reached if the first shaft is not successful he will usually sink further shafts towards the channel. Here again the element of luck will play a large part The first three shafts may prove profitless, but the fourth may produce sufficient gold to make ones hopes "spring eternal ' In alluvial gold-seeking the rewards correspond remarkably with the intelligence and magnitude of the effort made.
It does not follow that a gully or river-bed is non-auriferous because a few holes have been sunk in it without results it cannot be said to have been properly tested until the deposit in its bed has been thoroughly crossed from side to side and panned in several places Very frequently, too, the gold occurs, not in the gully bed but in some deposit on one of the banks Prospectors are therefore advised to carry out their preliminary work thoroughly before finally abandoning any easily prospected locality as worthless, even should they see evidences of it having been tried and left by others, before them.
HOW TO RECOGNISE BEDROCK.
A very brief inspection of old workings will toon enable the "new-chum" to recognise the bedrock of a river when he reaches it in sinking a shaft. It Is usually soft and decomposed just where the alluvial deposits rest on it, and in that condition is often known as "pipeclay" on account of its whiteness. A few feet further down, however, the slaty structure become visible, the rock gets harder, and the colour changes to yellow, grey, and other darker tints.
Down to this bottom the prospector sinks and takes up the stuff immediately resting on it with a few inches of the bottom Itself, as gold often lodges down in the crevices. In very shallow ground open trenches in various directions, or a number of holes at short intervals, are sufficient to enable the ground to be tested, but in deeper ground it is necessary to open drives from the bottom of the prospecting hole so as to try the stuff along the bottom in any direction desired. The object is to test the gravel resting on bedrock, as that is the most likely to contain gold. In some ground not a foot should be passed over without panning it, as it is not at all uncommon for cold to occur in certain narrow "runs," while promising looking stuff on either side is valueless.
While the Importance of working the gravel on the river bottom is greatly stressed, It is always advisable to pan any layer of gravel passed through In sinking a hole.
Old, abandoned ground, If it has not been too often reworked, will frequently be found to afford a living, or an occasional patch or nugget, if again carefully worked.
The Sydney Morning Herald
Saturday 28 February 1931
http://newspapers.nla.gov.au/
