|Quadrangle map, 1:250,000-scale||CR|
|Quadrangle map, 1:63,360-scale||A-1|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This site is about 0.3 mile south of James Lake and about 0.6 mile northeast of the center of section 6, T. 78 S., R. 89 E. It includes four prospects/claims about a half mile north of Dolomi. They were originally described between 1902 and 1908 but not since, and they probably have been incorporated into one or more of the nearby properties. The Beauty claim is the only one that can be confidently located, and that site (the one used for this record) is based only on a small-scale map by Wright and Wright (1908, figure 18). The other three claims or prospects adjoin, or probably are within 0.3 mile of, the Beauty claim.|
This site includes 4 similar deposits (Brooks, 1902; Wright and Wright, 1908). The deposit on the Beauty claim is in marble and consists of a quartz vein 12-18 inches thick that strikes N20W and dips 30SW. The vein contains chalcopyrite and tetrahedrite, and samples assayed up to $600 per ton in silver and $20 per ton in gold (at $20.67 per ounce). Another vein on the same claim strikes N20E and dips 20SE. The Beauty claim was explored by 2 shafts 45 feet deep and a drift that connected them.
The Home deposit is a quartz vein up to 2 feet thick that cuts fractured marble. The vein contains pyrite and tetrahedrite. At the Triangle #2 claim, a quartz-calcite vein 4 to 5 feet thick is exposed in a pit. The vein strikes N40W and dips 35NE. Samples assayed as high as $40 per ton (presumably in gold and silver). On the Welcome claim, a mineralized shear zone at the contact of schist and marble was said to contain free gold.
Most, if not all four, of these claims/prospects are probably included in what Herreid (1967) calls 'Prospects east of Amazon Lake,' 'Prospects east of central Amazon Lake,' and 'Prospects west of Amazon and James Lake.' However, his prospect names cannot be correlated with the names of the prospects at this site in the older literature. As in the old reports, Herreid repeatedly mentions the occurrence of tetrahedrite in many of the deposits in this area.The geology of the Dolomi area is dominated by an arcuate, generally north-trending, fault system and by a large dome centered over the eastern third of Paul Lake (Herreid, 1967). The Wales Group country rocks consist chiefly of several marble layers 200 to 1300 feet thick, interbedded with calcareous chlorite schist and marble.
|Geologic map unit||(-132.050131004079, 55.1400642194392)|
|Mineral deposit model||Low-sulfide gold-quartz vein (Cox and Singer, 1986; model 36a).|
|Mineral deposit model number||36a|
|Age of mineralization||Veins are younger than the Late Proterozoic or Cambrian host rocks.|
|Workings or exploration||Explored by pits and several shallow shafts with some minor underground workings.|
|Indication of production||None|
|MRDS Number||A010020; A010058; A010140; A010169|
Brooks, A.H., 1902, Preliminary report on the Ketchikan mining district, Alaska, with an introductory sketch of the geology of southeastern Alaska: U.S. Geological Survey Professional Paper 1, 120 p.
Herreid, Gordon, 1967, Geology and mineral deposits of the Dolomi area, Prince of Wales Island, Alaska: Alaska Division of Mines and Minerals Geologic Report 27, 17 p.
Smith, P.S., 1914, Lode mining in the Ketchikan region, Alaska: U.S. Geological Survey Bulletin 592-B, p. 75-94.
|Reporters||D.J. Grybeck (Applied Geology)|
|Last report date||5/1/2004|