| Quadrangle map, 1:250,000-scale | SR |
|---|---|
| Quadrangle map, 1:63,360-scale | A-3 |
| Latitude | 60.0493 |
| Longitude | -147.8995 |
| Nearby scientific data | Find additional scientific data near this location |
| Location and accuracy | The mine is located one-half mile southeast of Powder Point on the west side of Latouche Island. It is in the NE1/4 section 33, T. 1 S., R. 9 E., of the Seward Meridian. The Beatson mine is shown on the 1988 revision of the 1:63,360 U.S. Geological Survey topographic map. This is location 256 of Cobb and Tysdal (1980) and location S-17 of Jansons and others (1984). This location is accurate to within 300 feet. |
Geologic descriptionThe country rock in the mine area consists of a north-trending, interbedded sequence of west-dipping slate and graywacke, with graywacke predominating (Kurtak and Jeske, 1986). Nelson and others (1985) mapped this rock as Orca Group of early Tertiary age. The major structural feature in the mine area is the Beatson fault, which cuts slightly across bedding, strikes about N 12 E and dips (on average) 60 W. On the footwall of the fault, ore occurs as a massive and disseminated sulfide zone. The highest grade ore occurs adjacent to the fault (Kurtak and Jeske, 1986). The ore body is roughly 400 feet wide by 500 feet vertical and extends for 1,000 feet along strike. Sulfide minerals consist of pyrite, pyrrhotite, chalcopyrite, cubanite, galena, silver, and sphalerite; gold and silver are also present. Gangue minerals consist of quartz, sericite, and ankerite. The average ore grade was 1.7 percent copper and 0.27 ounce of silver per ton. Total production was 5,992,941 tons of ore grading 1.65 percent copper and 0.279 ounce of silver (Kurtak and Jeske, 1986). | |
| Geologic map unit | (-147.901517783894, 60.0486593561929) |
|---|---|
| Mineral deposit model | Besshi massive sulfide (Cox and Singer, 1986; model 24b) |
| Mineral deposit model number | 24b |
| Age of mineralization | Tertiary or younger; the mineralization is in rocks of the Orca Group of Tertiary age. |
| Alteration of deposit | There is strong silicification of the footwall rock. There is chloritic alteration of the hanging wall rock (Rogers and Hoyt, 1999). |
| Workings or exploration | From 1908 to 1930, the deposit was mined by both open cut and underground shrinkage stope methods. There were 10 miles of underground workings when mining ended in 1930 (Kurtak and Jeske, 1986). Improvements on the property included the town of Latouche, a wharf, and a diesel power plant. Production totaled 182,600,000 pounds of copper and 1,466,649 ounces of silver from 5,992,941 tons of ore. The average copper grade was 1.65 percent, and the average silver grade was 0.279 ounce per ton (Kurtak and Jeske, 1986). |
|---|---|
| Indication of production | Yes; large |
| Reserve estimates | Rogers and Hoyt (1999) report a reserve of 3,000,000 tons. |
| Production notes | Production totaled 182,600,000 pounds of copper and 1,466,649 ounces of silver from 5,992,941 tons of ore. The average copper grade was 1.65 percent, and the average silver grade was 0.279 ounce per ton (Kurtak and Jeske, 1986). |
| MRDS Number | A010628; A101673 |
|---|---|
ReferencesMartin, G.C., 1919, Alaska Mining Industry in 1917: U.S. Geological Survey Bulletin 692-A, p. 11-42.
Rogers, R., and Hoyt, M., 1999, Mineral prospects on Chugach Alaska Corporation lands: Chugach Alaska Corporation in-house report, 10 p., 1 table, 10 maps.
Smith, S.S., 1917, The mining industry in the Territory of Alaska during the calendar year 1915: U.S. Bureau of Mines Bulletin 142, 65 p.
Smith, S.S., 1917, The mining industry in the Territory of Alaska during the calendar year 1916: U.S. Bureau of Mines Bulletin 153, 89 p.
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| Reporters | Jeff A. Huber and Carol S. Huber (Anchorage) |
| Last report date | 12/18/2001 |