Mertie Lode

Prospect, Active

Commodities and mineralogy

Main commodities Co; Cu; Ni
Other commodities Ag; Au
Ore minerals chalcopyrite; magnetite; pentlandite; pyrite; pyrrhotite

Geographic location

Quadrangle map, 1:250,000-scale JU
Quadrangle map, 1:63,360-scale A-3
Latitude 58.234
Longitude -134.8573
Nearby scientific data Find additional scientific data near this location
Location and accuracy The Mertie Lode is at an elevation of approximately 1,700 feet, on the Mansfield Peninsula. It is 1 mile southeast of Funter Bay and 1 mile northwest of Mount Robert Barron, in the NW1/4 NW1/4 section 18, T. 42 S., R. 65 E. of the Copper River Meridian. The location is accurate.

Geologic setting

Geologic description

The Mertie Lode was discovered in 1919 by U.S. Geological Survey geologist J. B. Mertie during an examination of the Admiralty-Alaska Mine (JU224) (Reed, 1942). The deposit is in a gabbro-norite pipe that intrudes complexly folded, intercalated quartz-sericite schist, graphitic schist, and phyllite. The pipe consists mainly of sulfide-poor augite gabbro and norite; sulfide-rich olivine-hornblende gabbro is confined to the keel of the pipe. The keel contains up to 27 percent pyrrhotite, 2.6 percent pentlandite, 2.5 percent chalcopyrite, and 0.4 percent pyrite. The pipe plunges 30 degrees to the east and follows the contact between quartz-sericite schist and graphitic schist. The pipe varies in diameter from 60 feet to 200 feet and has been traced for 800 feet down-plunge (Chisholm, 1970; Reed, 1942; Wells and others, 1986). Two adits and 19 drill holes explored the Mertie Lode under a DMEA (Defense Minerals Exploration Administration) contract in the 1950s. The reserves are currently estimated to be 750,000 tons of ore with 0.5 percent copper, 0.5 percent nickel, 0.1 percent cobalt and 0.03 ounce of gold per ton (Chisholm, 1970; A. Pekovich, personal communication, 2000). The Mertie Lode is owned by the Admiralty-Alaska Mining Co., Inc. The owners are still actively (2000) conducting limited exploration on the property (Andy Pekovich, oral communication, 2000).
The rocks in the general area are mainly Ordovician and Devonian to Triassic clastic units, mafic-intermediate volcanic rocks, and subordinate limestone. The bedded rocks are intruded and locally metamorphosed by Cretaceous granodiorite (Gehrels and Berg, 1994).
Geologic map unit (-134.85909315596, 58.2336639396892)

Production and reserves

Workings or exploration Two adits and 19 drill holes explored the Mertie Lode under a DMEA (Defense Minerals Exploration Administration) contract in the 1950s. The Mertie Lode is owned by the Admiralty-Alaska Mining Co., Inc. The owners are still actively (2000) conducting limited exploration on the property.
Indication of production None
Reserve estimates The reserves are estimated to be 750,000 tons of ore with 0.5 percent copper, 0.5 percent nickel, 0.1 percent cobalt, and 0.03 ounce of gold per ton (Chisholm, 1970).

Additional comments

This prospect is under the same ownership as the Alaska-Admiralty (JU224) two-thirds of a mile to the northwest, and is sometimes shown as the same property.

References

MRDS Number A010691; A012087

References

Chisholm, E.O., 1970, Examination report on Admiralty Alaska nickel-copper deposit, Funter Bay, Admiralty Island, Alaska: Unpublished private report for Northgate Explorations, 26 p.
Gehrels, G.E., and Berg, H.C., 1994, Geology of southeastern Alaska, in Plafker, George, and Berg, H. C., eds., The geology of Alaska: Geological Society of America, DNAG, The geology of North America, Vol. G-1, p. 451-467.
Reporters J.C. Barnett and L.D. Miller (Juneau, Alaska )
Last report date 12/15/2001