Work History

Staked as Dorothy (38807) and Rocket cl (14457) in Dec/21 by G. Gray and D. Horne and as Tyee cl (16038) and Rocket cl (16575) in Jul-Sep/25 by H.E. Formo and A. Stewart. Formo explored both claims with shafts and drifts from 1929-31 when 36.3 tonnes of ore were shipped. The claims were taken to lease (Lots 273 and 274) in Sep/34 and renewed in Sep/55.

Silver Basin Mines Ltd optioned the property in 1947, shipped 54.4 tonnes of ore later in the year, and purchased the claims in Nov/48. The claims were transferred in Jan/50 to Consolidated Yukeno Mines Ltd and in Feb/51 to Yukeno Mines Ltd, which carried out underground development in 1952-53. Over 1 219.2 m of drifting and crosscutting, plus minor raising and shaft sinking, were completed on three levels.

A.A. Smith leased the property in 1961 and shipped 13.4 tonnes of ore. In 1962, the property was purchased by Rio Plata Silver Mines Ltd, which explored with 13 x-ray holes (205.1 m) and bulldozer trenching in 1964; more trenching, EM surveying, underground rehabilitation and drilled 8 holes (274.3 m) in 1974; and percussion drilling in 1975.

During this period A.D. Ross restaked the Something cl fr (Y84831) in Aug/73, which was a relocation of a former surveyed mineral claim of the same name located immediately south of the Dorothy claim. In the autumn of 1973 Rio Plata carried out magnetometer surveying and geochemical soil sampling of the Formo property including the Something cl fr which had been earlier acquired form Ross. Ross also staked the Ross cl (Y85975) 2 km to the south in Oct/73 and after acquiring this claim (part of their Aztec group) Rio Plata carried out geochemical soil sampling of the claim in 1973 and 1975.

In 1980-81, the 2 700 level adit was rehabilitated and the southerly extension was explored with 54 percussion holes (2 647.2 m) and 6 core holes (289.6 m). The property was leased in Feb/82 to J.B. O'Neill, who mined about 71.7 tonnes of ore in 1983.
In Apr/83, the Rocket claims were transferred to Reflection Resources Ltd. The adjacent Rex, Pro, Abel, Cain (YCML 1044) and Horseshoe claims to the west were acquired in Feb/80 by Canada Tungsten Mining Corporation Ltd, which carried out geochemical soil sampling, before transferring the claims to Springmount Operating Company Ltd in May/87.

In Jun/86, all of Rio Plata's claims in the district were optioned to Dawson Eldorado Mines Ltd which carried out trenching later in the year.

Silver Quest Resources acquired 13 mining leases over and surrounding the original occurrence. Surface samples of mine materials were assayed to confirm historical values.

Capsule Geology

Erratic narrow lenses of galena, sphalerite and minor tetrahedrite occur in carbonate gangue within a typical narrow, north-trending, transverse vein cutting schist and greenstone beneath the Keno Hill Quartzite. The 1973 trenching explored a 213 m interval along the structure and is said to have exposed a mineralized zone 45.7 m long grading from 2 057.1 to 3 257.1 g/t Ag across a 1.2 m width.

The 1975 percussion drilling located a new vein 180 m northwest of the main vein. Formo's 1931 shipment graded approximately 7 886 g/t Ag Ag and 60% Pb. The 1961 shipment graded 4 957.6 g/t Ag, 57% Pb and 10.3% Zn. Campbell estimated proven and probable ore reserves in 1965 at 39 917 tonnes grading 548.6 g/t Ag, 6.9% Pb and 10.7% Zn but regarded this estimate as optimistic, a similar figure of 40 000 tonnes grading 550 g/t Ag, 6.9 % Pb and 10.7% Zn was reported in 1989 (Morin, 1989).

The 1980-81 drill program showed that mineralization is restricted to the Formo showing and failed to locate any new ore missed in the underground workings. The best intersection assayed 2290.2 g/t Ag and 1.0 g/t over 48 cm. Erratic gold values up to 17.1 g/t were obtained from a few of the vein intersections. O'Neill mined a 90 cm wide lens of galena near the 1930 shaft and the first 48 tonnes of his shipment graded 4909.6 g/t Ag, 57.4% Pb and 9.6% Zn.

Sampling of the old mine dump on the property by Silver Quest Resources in 2009 confirmed historical values with rock assay results of 3025 g/t Ag, 0.096% Cu, 15.85% Pb and 39.80% Zn.

References

CANADIAN MINING JOURNAL, Feb/50, p. 80.

DAWSON ELDORADO MINES LTD, Feb/87. Assessment Report #092159 by P.D. Van Angeren and P.S. White.

GEOLOGICAL SURVEY OF CANADA Bulletin 111, p. 21-22.

GEOLOGICAL SURVEY OF CANADA Paper 62-27, p. 27; 63-38, p. 10.

GEORGE CROSS NEWSLETTER, 24 Sep/73; 24 Dec/75.

MINERAL INDUSTRY REPORT 1974, p. 12-13.

MORIN, J.A., 1989. Yukon Gold-Silver File. Exploration and Geological Services Division, Yukon, Indian and Northern Affairs Canada, Open File 1989-3.

MURPHY, D.C. and ROOTS, C.F., 1996. Geological map of Keno Hill area, Central Yukon (105M/14). Exploration and Geological Services Division, Indian and Northern Affairs Canada, Geoscience Map 1996-5, scale-1:50 000.

MURPHY, D.C., 1997. Geology of the McQuesten River Region, Northern McQuesten and Mayo Map Areas, Yukon Territory (115P/14, 15,16; 105M/13, 14). Exploration and Geological Services Division, Yukon, Indian and Northern Affairs Canada, Bulletin 6, 122 p.

RIO PLATA SILVER MINES LTD, May/75. Assessment Report *#061269 by K.L. Daughtry.

RIO PLATA SILVER MINES LTD, May/75. Assessment Report *#061270 by K.L. Daughtry.

RIO PLATA SILVER MINES LTD, 1975. Assessment Report *#090063 by K.L. Daughtry.

RIO PLATA SILVER MINES LTD, Jan/76. Assessment Report *#090064 by K.L. Daughtry.

ROOTS, C.F., 1997. Bedrock geology of Mayo map area, central Yukon (105M). Exploration and Geological Services Division, Indian and Northern Affairs Canada, Geoscience Map 1997-1, 1:50 000-scale.

ROOTS, C.F., 1997. Geology of the Mayo Map Area, Yukon Territory (105M). Exploration and Geological Services Division, Yukon, Indian and Northern Affairs Canada, Bulletin 7, 82 p.

SILVER QUEST RESOURCES LTD., News Release, 17 Jun/09.

YUKON EXPLORATION 1988, p. 122-124.

YUKON EXPLORATION AND GEOLOGY 1981, p. 167.

 

Assessment Reports that overlap occurrence