The Molly showing is located south of the western end of Williston Bay (Atlin Lake), 47 kilometres southwest of Atlin. The Molly South showing (104M 051) is 750 metres to the south.
In the area, Early Jurassic Aishihik Plutonic Suite rocks comprising foliated hornblende granodiorite to quartz diorite, is intruded by Coast Plutonic Complex rocks comprising Early Cretaceous biotite granite and granodiorite and Late Cretaceous biotite-hornblende granite to alaskite. Quartz and quartz-carbonate veins are ubiquitous in the vicinity of alaskite bodies, which also contain marginal silicified breccias with alaskite and quartz fragments. Biotite granodiorite is strongly fractured near alaskite contacts.
Molybdenite occurs in fractured granodiorite, quartz veins, and to a lesser extent in alaskite and breccias as patches, rosettes, and fine disseminations. Chalcopyrite is common and minor tetrahedrite, magnetite, stibnite, and galena occur locally. Argillic alteration is most intense in mineralized areas, and locally strong sericitization and silicification have created coarse greisen zones.
WORK HISTORY
The earliest work in the area was at the turn of the century on the Laverdiere property (104M 022). The Callaghan vein (104M 021) was discovered in 1910. The Molly showings (104M 029, 051) were discovered in the late 1950s to the southwest of the Callaghan.
In 1964, Cominco Ltd. staked 48 claims in two groups, the Molly 13 and Molly 14. During 1964, geological mapping, a magnetometer survey, trenching, and 366 metres of BX diamond drilling was carried out. In 1965, an additional 457 metres of diamond drilling was completed in 3 holes. In 1970, the property comprised 54 claims as the Molly and Faye groups. Work by Cominco during 1970-1971 included geological mapping, a geochemical silt survey, and rock sampling for trace element analysis. In 1972, 13 line-kilometres of induced polarization survey was carried out over 13 Molly claims. During 1974, diamond drilling was completed in 4 holes totalling 644 metres on the Molly 11, 12, and 30 claims.
In 1989, prospecting and sampling was conducted on the Ara property, which covers the Molly showings, by Equity Silver Mines (Figure 3, Assessment Report 20134). The prospecting was carried out over an area of 0.6 square kilometres on the NA 4666 and NA 4866 claims, while 13 9-kilogram-heavy mineral sediment samples were extracted from creeks draining the NA 4868, NA 4870, NA 5070, NA 4666, and NA 4866 claims, all of which drain either north or south into Willison Bay. Thirteen rock samples were taken in the course of prospecting. Two of these were of drill core stored at Cominco's campsite on Willison Bay. Of the thirteen heavy mineral concentrates taken from creeks draining the property, two samples, Atlin BG-01 and SH-01, are considered significant. The former sample was extracted from Eric Creek, which drains several mineralized showings (Figure 3, Assessment Report 20134). It is probable that the gold in this concentrate was derived from one or more of these showings. The latter sample was taken on an unnamed creek draining south into Willison Bay. As little prospecting has been done in this area, it is difficult to determine the source of the gold in this highly anomalous concentrate though it should be noted that the creek approximates the Llewellyn fault zone.
Refer to Callaghan (104M 021) and Laverdiere (104M 022) for related information.
