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Tidbits on BC Placers

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Old Rivers:
CHRONOLOGY OF BRITISH COLUMBIA PLACERS

The following chronological table gives the discovery dates of the principal creeks and diggings:--

1852-Chief Trader McLean, of the Hudson’s Bay Company, purchased gold dust from
Indians at Kamloops.
1855-Gold discoveries on the Columbia at the mouth of the Pend d’Oreille River.
1857“Coarse gold discovered at the mouth of the Nicomen River, tributary to
1858-Gold first discovered in quantity on the lower Fraser River, at Yale.
1860-Rock Creek in Boundary District discovered.
1860-First discoveries in Cariboo area, on Quesnel River and on Keithley and
1861-Williams Creek and Lightning Creek strikes made.
1861-Gold discovered on the Parsnip River.
1863-Placers found on Wild Horse River, East Kootenay. the Thompson, above
Lytton. Antler Creek.
1863-This was the year of greatest development and output of the Cariboo .

Maximum official recorded production in the history of the Province

1864-Leech River placers discovered on Vancouver Island .
1S69-Vital Creek, tributary of Omineca. discovered .
1865-Gold discovered on French Creek in the Big Bend of the Columbia River .
1873-Gold discovered on Dease and Thibert Creeks .
1879-Hydraulic mining on a large scale commenced in Cariboo .
1885-Placer strike made at Granite Creek, Tulameen River .
189S”Atlin placer fields discovered .
1921-Rich strike made at Cedar Creek .
1924-Gold found on Goldpan Creek .
1927-Coarse gold found by Indians on Squaw Creek .
1932-Initial discovery of &old on Wheaton (Boulder) Creek .


BRITISH COLUMBIA PLACER-GOLD PRODUCTION
Year       Crude 0 1 .
1858-1862 ............ 580.680
1863-1867 ............ 957. 860
1868-1872 ............ 582. 080
1873-1877 ............ 530. 540
1878-1882 ............ 328.?30
1883-1887 ............ 225.970
1888-1892 ............ 148. 550
1898-1903              374. 740
1893-1897              135. 340
1904 ................ 65. 610
1905 ................ 57. 020
1906 ................ 55. 790
1907 ................ 48. 710
1908 ................ 38. 060
1909 ................ 28.060
1910 ................ 31;760
I911 ................ 25. OM)
1912 ................ 32.680
1913 ................ 30. 000
1914 ................ 33. 240
1915 ................ 45. 290
1916 ................ 34. 150
1917 ................ 29. 180
1918 ................ 18. 820
1919 ................ 16. 850
1920 ................ 13.040
1921 ................ 13. 720
1922 ................ 21.690
1923 ................ 24;710
1925 ................ 16.476
1924 ................ 24. 750
1926 ................ 20. 912
1927 ................  9, 191


PLACER DEPOSITS

Unconsolidated material containing gold or other valuable minerals in sufficient quantity to be of economic interest is called a placer deposit . Any heavy mineral that resists mechanical destruction owing to its hardness or malleability. and responds slowly to chemical change. is apt to be concentrated in placers . Placer deposits may contain such minerals as gold. platinum. metallic copper. magnetite (black sand).


PLACER-MINING IN BRITISH COLUMBIA

ilmenite, garnet, pyrite, hematite, occasionally galena, zircon, scheelite, tourmaline, stream-tin (cassiterite), and gem stones. In British Columbia, placers have been worked for gold, and a few for gold and platinum or principally for platinum.

Placer-gold deposits are formed by the natural Concentration of the weathered products of gold-bearing rocks. During the course of weathering, rocks are broken down by the combined processes of mechanical disintegration and chemical decomposi-tion. The more resistant minerals are little changed other than to be broken into various small-sized fragments while the less resistant minerals are made over and partly dissolved. As a result, grains of quartz, magnetite, gold, etc., are set free from the rock-mass, while the grains of feldspar and of ferro-magnesian and other minerals may be transformed into clay-like minerals, iron oxides, and soluble salts. When this disintegrated and decomposed material is subjected to the sorting action of water, the lighter minerals are carried farther downstream. The gold contained in a paystreak resistant minerals of high specific gravity are deposited near their source while the is derived from the concentration of a very large volume of rock.


RESIDUAL PLACERS

In the course of weathering, part of the deposit is dissolved and carried away in solution. Residual placers may be formed at the weathered outcrops of gold-hearing deposits, and part is disintegrated and carried away by run-off water. Gold, being heavy and inert, tends to remain at or close to its original position and is concentrated at the outcrop. Run-off water removes a relatively small amount of material; the richness of a residual placer, therefore, depends upon the richness of the original lode. In British Columbia, residual placers are of little importance because rapid erosion has dispersed the parts of most lodes that had been weathered in pre-glacial times, particularly those parts lying in exposed positions above valley bottoms. Nevertheless, in the early prospecting for outcrops of gold-bearing veins in the Bridge River and Wells mining camps some residual concentrations were found and were worked as placers.


STREAM PLACERS

British Columbia placers have formed largely as a result of stream concentration. The disintegrated material from a gold-bearing lode gradually moves downhill underrunning water results in small fragments and material of lower specific gravity being the influence of slope wash until it reaches a stream channel. The sorting action of moved selectively downstream. I n addition, the material in the stream bed is continually being agitated so that the minerals of high specific gravity tend to work down, eventually becoming concentrated in the creek bottom. Nuggets of gold sink rapidly through the gravel without traveling far downstream. Fine gold is gradually and continuously carried farther, and very fine flaky gold may be carried many miles down-stream, the formation of placers. Where a stream is down-cutting, bedrock is being scoured. During its life history a stream may pass through a number of’ stages that affect stream flattening of the grade, overloading of the stream, or slackening of the current and any gold lodged on it gradually moves downstream. In other sections of the on the inside of a bend will cause gravel and gold to be deposited owing to the lessened carrying power of the water. In some sections the stream may swing from one side material on the inside. Bars form in large creeks during certain stages, and fine gold of the valley bottom to the other, eroding on the outside of a curve and depositing that is carried by the flood-waters is deposited on them.

All streams have a sorting action upon the gravel in their beds, but extremely rich placers are formed only by the concentration of gold released from lodes during long periods of weathering and stream erosion.

In British Columbia, active down-cutting by streams took place in late Tertiary rock benches, on some of which the gravel is rich enough to be mined profitably. or early Pleistocene time, with the result that stream valleys were deepened, leaving The formation of British Columbia placers bas been greatly affected by glaciation.
Normal development of placers in many mountain streams has been greatly modified; in numerous places gravel has been dispersed, bedrock eroded, and a layer of boulder clay deposited by valley glaciers. Overloading of streams and disturbances of drainage brought about during interglacial and postglacial times have complicated both the formation of placer deposits and the search for them. In the early stages of glaciation, before there was much accumulation of ice, there was undoubtedly an increased precipitation and a high run-off during the summer months. This run-off swept much of the weathered rock debris and residual gold deposits into the valleys. The valleys were filled in many instances to depths of several hundreds of feet with this material. Many streams were unable to transport the tremendous load supplied to them, with the result that previously formed placers were buried to considerable depths, places cut through rock-spurs projecting into the old valleys. Since the final retreat During interglacial periods the streams cut down through these deposits and in of the ice, streams have again cut down their channels in the filled valleys and locally in bedrock. Most present-day streams follow old valleys, in part at least, but in some instances streams have completely abandoned their former valleys. Stream activity during interglacial periods and in recent time caused the erosion richness. Old gravel-filled channels, possibly cut through and partly destroyed by later of some earlier placers and their re-deposition as placers of various ages, origin, and streams in a valley, may still remain as bench deposits, deep leads, or buried channels, higher or lower than the present stream bed. surface enrichments extending only to shallow depths. Postglacial streams have reworked older gravel and boulder-clay deposits to form beach placers.


BEACH PLACERS

Beach placers are formed by a combination of the concentrating action of long-concentrations of gold and black sand are formed only when the wind and the waves shore drift, currents, tides, and waves upon gold-bearing sands and gravels. Local are from particular directions. Concentrations rich enough to be worked are usually
small, and considerable difficulty is often experienced in separating the exceedingly Bay, Vancouver Island, and on the east coast of Graham Island. small, rusty flake gold from the magnetite sand. There are beach placers at Wreck Bay, Vancouver Island, and on the east coast of Graham Island.


CHARACTERISTICS OF PLACER GOLD

Gold particles that are rough and hackly or have adhering quartz prove that the gold has not been much worn and indicate that the gold is close to its original source. Gold that is pounded and worn into smooth flat nuggets or flakes has traveled some considerable distance from its source. These characteristics apply regardless of the size of the individual pieces, although the finer sizes naturally travel farther, and fine flaky pieces will travel farther than rounded or shot-like pieces of equal weight.

An almost constant characteristic of placer gold from any one creek is its fineness -i.e., the gold-silver ratio. In British Columbia, placer gold ranges in fineness from parts for gold from Goat River. Most placer gold ranges from 800 to 900 fine. The about 700 parts per 1,000 for gold from Cherry and Monashee Creeks to about 970.
The numerical average of the average fineness of gold from 173 streams is 861.

Placer gold is an ally, mainly of gold and silver, but may contain small amounts of platinum, copper, iron and other elements. Its color depends mainly on the amount of silver present, and also on the presence or absence of surface films of iron oxide. The color, size, and general shape of the gold pieces present. so characteristic an appearance that experienced gold-buyers can tell from which creak any packet of gold has come.


SIZE OF PLACER GOLD

Placer gold occurs in sizes ranging from large nuggets to minute particles requiring many thousands to yield a value of 1 cent. Pieces valued at more than 5 to 10 cents are spoken of as nuggets. Coarse gold will not pass through a IO-mesh screen, will pass through a 40-nlesh screen. These figures refer to standard screens in which and fine gold will be retained on a 40-mesh screen. Flour gold includes all sizes that there are 10 and 40 openings per lineal inch. The Cariboo was remarkable for its coarse gold, whereas mostly fine and flour gold was recovered from. the bars and benches of the Fraser River below Hope, and from the Peace River.

Nuggets are formed from plates and masses of gold which have been released from lode deposits by weathering, and pounded and rolled into solid lumps. The recovery of large pieces of gold from lode-mining at Cariboo and Bridge River demonstrates that gold-bearing veins contain gold of sufficient size to form large nuggets. There is no evidence to show that chemical deposition of gold in the gravel has played any part in the formation of placer-gold nuggets.

Of the large nuggets found in British Columbia, there is record of one weighing about 72 ounces, valued at $1,300, found on McDame Creeck in 1877; it is probably the largest all-gold nugget found in the Province. Dease Creek yielded one of about 60 ounces, valued at $800, in 1875. A quartz and gold nugget, found on Spruce Creek in found. In 1931 one weighing 73 ounces and valued at $1,200 was found on Birch 1899, weighed 85 ounces, and in 1901 one weighing 36 ounces 12 pennyweight was Creek. Germansen Creek in 1935 yielded a nugget of about :24 ounces. In 1937 a nugget weighing 52 ounces 15 pennyweight was found on a tributary of Wheaton A nugget valued at $900 was found on Lockie (Boulder) Creek in 1887 and one
(Boulder) Creek and also one weighing 46 ounces 5 pennyweight on Squaw Creek. weighing 32 ounces found about 5 miles up the Bridge River.

The largest nugget, of which there is record, from the Cariboo was found in 1864 on Butcher Bench, Lightning Creek, and weighed 30>{, ounces. Wild Horse River yielded a nugget weighing 37 ounces.


MINERALS ASSOCIATED WITH GOLD IN PLACERS

Placer concentrates are frequently composed largely of black. and. The black sand is chiefly magnetite but may include small amounts of ilmenite and chromite. In the Cariboo, sluice-box concentrates contain very little black sand, being composed mostly of cube iron (pyrite) and, on some creeks, abundant galena. Brown and red garnets are found in placer concentrates from Quesnel and Tulameen Rivers. Platinum is associated with gold in some British Columbia placers, and in some localities has been equal to or greater than the amount of gold. Platinum has been recovered in some quantity from the Tulameen River. It also occurs with placer gold
on Pine, Thibert, McConnell, Rainbow, Tranquille, Rock, and Government Creeks. Small amounts of platinum are recovered with the gold from placers along the Quesnel, Fraser, Cottonwood, Peace, and Coquihalla Rivers; it occurs also on the North Thompson River at the mouth of the Clearwater River.

Small amounts of platinum have been recovered from the beach placers on Graham Island. No platinum is known from the placer creeks in the vicinity of Barkerville.

Zircon and scheelite are found in placer concentrates. Scheelite is not uncommon in grains up to bean size in placer creeks around Barkerville. Prospectors have discovered in panning that an occurrence of scheelite will throw a train of small particles for considerable distances.

Wolframite and cassiterite have been recovered from placers on Boulder Creek, Atlin

Arquerite (a natural silver amalgam) occurs in the gold placers on Vital, Tom, Harrison, Silver, and other creeks in the Ominica; it is also reported from the mouth on Tahltan River.

Cinnabar in appreciable amounts has been recovered by placer-miners on the Quesnel River near Quesnel Forks. The greatest amount appears to have been obtained near the mouth of Four Mile Creek.

A somewhat uncommon mineral, awaruite (a nickel-iron alloy), has been recovered from Bridge River, Fraser River near Lillooet, and Wheaton (Boulder) Creek. Nuggets of native copper are recovered in some placer concentrates. Pieces weighing as much as 15 pounds have been found on Squaw and Thibert Creeks.
A nugget of native silver was recovered from a creek tributary to Kehlechoa River in 1945. Other heavy minerals, such as barite, hematite, or epidote, form part of the placer concentrates from various creeks.

No native mercury is known from British Columbia placers, although gold in part covered with quicksilver has been recovered from old workings where the mercury was evidently spilled by miners.

Shot, coins, nails, solder, and a variety of other metal objects are recovered when
reworking old ground or sniping around old diggings. No recovery of gem stones from British Columbia placers has been recorded officially.


DISTRIBUTION OF GOLD IN PLACERS

Gold in gravel or sand will migrate downward as long as the material is loose and is agitated by flowing water. As a general rule the gold settles until it reaches bed-rock, consequently the paystreak in many instances rests on bedrock.* If the down- ward movement of the gold is stopped at a clay layer or a bed of tightly packed gravel some distance above the actual bedrock, a paystreak may be formed on what is termed false bedrock.

Gold is seldom uniformly distributed through the gravel, and as a consequences the prospector is usually searching for a workable paystreak. In most bars and in some grade or barren. The boulder clay of glacial deposits is commonly almost devoid of bench deposits it is the upper gravel that is enriched while the lower material is low in gold, but in some rare instances masses of gold-bearing gravel have become incorporated in it.

The outline and position of a paystreak depends on a number of factors, of which the most important is the stream history. Many possibilities for concentration are provided by complex drainage histories, the various factors involved in placer formation, and the complicating effects of glaciation. There is no absolutely certain way of predicting the occurrence of a paystreak. A study of the stream history is helpful in formulating a working hypothesis, but test work must ultimately be done in order to prove the existence and define the position of a paystreak.

The richest section of a placer deposit is most apt to be close to the source of the gold or in some place where there has been a greater than ordinary amount of concentration. Stream placers in general are found to become lower in grade and contain smaller particles of gold when followed downstream. Points of greater concentration will occur where a stream crosses and erodes a higher gold-bearing: deposit. Paystreaks may form on the inner sides of river bends or on bars, or in any slack water where the gold particles are dropped. A paystreak may branch, reflecting a change in course of the stream, a second run of gold, or the entrance of a tributary into the main channel. Paystreaks may terminate abruptly because of steepening in grade of the stream or change in character of bedrock, or by having been eroded either by stream or ice action. It is only after considerable mining experience on a single placer deposit or on a single creek that the vagaries of a paystreak may be predicted in advance.

* However, gold will penetrate into any crack or crevice, and this fact should be kept in mind when cleaning up bedrock.


PLACER-MINING POSSIBILITIES

Placer-gold production has generally declined since the peak production in 1863. There are, however, local peaks which indicate increased production due to new discoveries, new methods of working, and to the increase in the price of gold from 1932 to 1940. Known placer deposits are progressively being worked out and important new discoveries are infrequent, consequently it is probable that placer-gold production will continue slowly to decline. Nevertheless, possibilities do exist for the discovery of virgin creeks or of ancient and hitherto unknown channels in old camps. Important new finds, such as those on Cedar Creek in 1921, Squaw Creek in  1927, and of coarse gold on Wheaton (Boulder) Creek in 1937, suggest that the possibility is not too remote. Ancient channels, either buried or elevated, are apt to be suspected around an old placer area, but the proof of their existence and their testing for workable values may constitute an undertaking of considerable difficulty and expense.

Other possibilities exist in the adaptation of new methods of working to deposits already known. Mechanical methods of mining using the latest and cheapest dirt-moving equipment and techniques might be applied to deposits that in the past could not have been worked profitably. An example of a new technique: is the dragline dredge that is so successful in working certain types of deposit. Opportunities also exist for the development of a technique for the successful mining of deep leads, such as those on Lightning Creek, as well as for the working of small yardages of bench deposits remote from water and too small to warrant a dragline-dredge operation.

In established camps, as old operations cease and water rights are relinquished or transferred, water in volume may become available for the hydraulicing of other deposits that hitherto have been handicapped by a shortage of water.

Finally, for the individual there is always sniping. Just so long as there are men with ideas as to where gold my be found, and just so long as there is bedrock to be cleaned and there are men who would rather work for themselves than for someone else, sniping will continue. The number of men at work sniping varies considerably with economic conditions. When work is plentiful or wages are high the number diminishes but when work is scarce and unemployment is general the number increases many times. In the Cariboo and on the Fraser and Quesnel Rivers, even ninety years after the discovery of gold, places still remain on the bars and benches and on bedrock where a man may work and recover some gold.

Sniping is an art in itself. It may mean cleaning bedrock that was not thoroughly cleaned in the original operation, or reworking old tailings that contain recoverable gold. For example, when water is scarce boulders from a drift operation may not be thoroughly washed, or when the gravel is clayey sufficient water may not be available to break up the balls of clay that will roll through the sluice-boxes and rob them of gold. In other instances it may mean doing a lot of dead work to reach a piece of virgin ground that because of low values or some other reason was left un-worked by the old-timers. It may mean waiting for extreme low water in order to get out on to river bars to skim the upper few inches of sand and gravel. Sniping means hard work, but at the same time it offers a livelihood and promises independence for the individual.

Re-print from BC Dept of Mines (1932 & 1956)

OR

blackrosejay0918:
The chronological table gives the discovery dates of the principal creeks and diggings were great.

Travisdjtg:
Thnx  ;D that was a good read.

Kagezan:
Very informative - thanks!

Delmar:
That is the kind of stuff I like to read. Thanks :)

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