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      The Origin of the Gold
 Written expressly for the Klondike Nugget by J. Sloan Johnson. The gold on Bonanza and Eldorado creeks originated principally in the track 
of the glacier that parallels those streams.  The glacier traveled from a 
northerly direction following a formation commonly known as prophyritic quartz, 
which is about 800 feet wide and which lies about 150 feet higher than the 
present bed of the two creeks mentioned. The formation over which the glacier traveled is composed principally of 
igneous rocks mixed to a certain extent whith metamorphic rocks.  The 
formation of the gold belt is very similar to that of California, and the gold 
found in the alluvial deposit has at some time been connected with the dikes of 
dissimilar rock and with the quartz veins and stringers crossing and connecting 
with each other throughout the gold-bearing formation. We will mention a few formations crossing the great dike covered by the 
gravel.  Commencing opposite No. 25 below on Bonanza, on Fox gulch, we find 
small stringers of rhyolite crossing the main formation at right angles.  
On 19 gulch we find an intrusive dike, commonly known as pegmetite; this occurs 
on the bench claim opposite the upper half of No. 3, left limit.  On the 
upper half of No. 3, Magnet gulch, we find the pure porphyritic quartz, largely 
interlaced with quartz stringers.  On the benches opposite No. 12 below, 
Bonanza, mica schist intrudes itself into the main dike and forms the bed rock 
of the benches.  At No. 5 below Bonanza, we encounter the graphite shists 
crossing the benches at right angles.  This is found in great abundance on 
Cheechaco hill. Passing to Big Skookum, we find a cross section of choloritic shist.  
This formation traverses Gold hill and has much to do with the rich deposit of 
gold found there. Between No. 13 and No. 14 Eldorado, we encounter a diabase dike crossing the 
formation. On French hill we have black slate, talcose slate and plumbago shist. On upper Eldorado, porphyry occurs quite frequently, together with mica shist 
and plumbageo shist. These formations are intrusive, and at the point of contact with the quartz 
veins and stringers form what are known as quartz pockets.  And when the 
gravel is removed from the hills and the bedrock exposed, the pocket miner will 
then uncover the richest pockets the world has ever seen. French hill, Gold hill and Cheechako hill give evidence of wonderful pockets 
in the quartz.  The glacier wore the formation down and turned the pockets 
inside out and deposited the gold on bedrock.  The pick and drill will 
delve into the quartz stringers and find pockets of fabulous richness when the 
pocket miner can see the formation and find the stringer on which to sink. A peculiar feature of the coarse gold streak in the high benches is that 
native quicksilver is found from Fox hill to Gold hill.  Also we find along 
the line of the glacier drifts, especially about the sixties below on Bonanza, 
many specimens of casseterite or stream tin.  This follows with the heavy 
gold.  This is very rich in tin, assaying 67 per cent tin.  We think, 
judging from the peculiar geological structure of the country that the great 
wealth of Bonanza and Eldorado districts lies under the alluvial deposit of the 
high benches, and when transportation companies will sell powder and steel at a 
reasonable profit, and the government be more liberal in its policy, then the 
resources of this country will be developed.  We do not look for milling 
quartz, but the wealth of the country lies in the bull quartz or pocket, where 
it makes a crossing with other veins or dikes; and instead of heavy machinery 
being necessary, the miner with a hand mortar can separate the gold as we do in 
California. The Klondike Nugget,
November 1, 1899. |