QUICKSILVER, PLATINUM, TIN. TUNGSTEN, CHROMIUM, 
AND NICKEL. 
Of the metals here grouped only two — quicksilver and chromium — 
are at present worked on a large scale in the United States. The 
papers on tin and tungsten presented below are reprints, in slightly 
condensed form, of reports which have recently appeared in Survey 
publications. A description of the Rambler copper mine, in Wyoming, 
is included, as platinum has recently been discovered in the ores of 
this mine. 
STREAM TIN IN ALASKA. 
By Alfred H. Brooks. 
White studying the gold placers at York, on the Seward Peninsula. 
Alaska, the writer's attention was called to the occurrence of stream 
tin (cassiterite) in the placers. The stream tin was found at two 
localities in the region. The first is on Buhner Creek, a westerly 
tributary of the Anikovik River. The mouth of Buhner Creek is 
about 3 miles from Bering Sea. The occurrence is best located by 
stating that it lies about 10 miles east of Cape Prince of Wales, and 
very near the northwestern extremity of the continent. On Buhner 
Creek 2 to 3 feet of gravel overlies the bed rock, which consists of 
arenaceous schists, often graphitic, together with some graphitic 
slates. The bed rock is much jointed, the schists being broken up 
into pencil- shaped fragments. They strike nearly at right angles to 
the course of the stream and offer natural riffles for the concentration 
of heavier material. A hasty reconnaissance of the drainage basin 
of this stream, which includes not more than a square mile of area, 
showed the same series of rocks throughout its extent. At a few 
localities some deeply weathered, dark-green intrusives were found, 
probably of a diabasic character. The slates and schists are every- 
where penetrated by small veins, consisting usualty of quartz with 
some calcite, and frequently carrying pyrite and sometimes gold. 
These veins are very irregular, often widening out to form blebs, and 
again contracting so as not to be easily traceable. 
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