Molly Gibson vein follows a northwest striking joint set in potassium-feldspar porphyritic granite. Workings explore two veins, the Florence and Aspen - they strike 145 degrees and dip 75 degrees. Ore shoots plunge to the southeast at about 45 degrees. Wallrock alteration includes pervasive propylitic, argillic, and locally hematite alteration. Vein mineralization comprises galena, sphalerite, arsenopyrite, pyrite, and chalcopyrite in a gangue of brecciated manganese rock, siderite, and quartz. Vein textures and mineralogy suggest several stages of brecciation and mineralization. A grab sample taken in 1987, assayed 2300 grams per tonne silver, 0.51 grams per tonne gold, 0.205 per cent copper, 9.1 per cent lead, and 3.93 per cent zinc.
The property is located on the west side of Kokanee Peak, in Kokanee Glacier Provincial Park, some 26 kilometres northeast of Nelson.
The date of discovery is not recorded although the Report of the Minister of Mines, 1922, states that shipments of high-grade ore were made as early as 1890. The Molly Gibson, Aspen, and Florence claims were optioned to Hon. Rufus, H. Pope in 1896. The Molly Gibson Mining Company, Limited was incorporated in British Columbia in November 1898. Six claims, the Aspen (Lot 1578), Molly Gibson (Lot 1579), Florence (Lot 1716), La Plata Fr. (Lot 1719), Little Dike (Lot 4392), and Little Fraction Fr. (Lot 4393) were Crown-granted to the company in 1901. During 1902 mining operations were carried out under contract, some 1800 tonnes of ore being shipped to the Nelson smelter. A snow slide ended operations late in 1902 and work was not resumed until 1904.
A new company The La Plata Mines Company Limited, was incorporated in April 1909 to operate the property. A 100-ton per day concentrator was built on Kokanee Creek, with a mile tramline to connect with the mine. Milling began in July 1906 and continued through 1907. Due to financial difficulties the company was dissolved in 1908.
The Consolidated Mining and Smelting Company of Canada Limited acquired the property in 1910 by payment of 2,000 treasury shares. A second tramline 7.2 kilometres long was built to replace a portion of the road between the mill and the west arm of Kootenay Lake. The mine and mill were operated intermittently until early 1920. Underground development work to 1920 totalled 2743 metres of drifts, crosscuts, and raises in 5 adits, the 5th level being at 2103 metres elevation. Lessees operated the mine and mill intermittently until 1926.
The company resumed development work in 1930. A new low level crosscut adit begun at the 1792-metre elevation had been driven for 564 metres in 039 direction when work ceased in 1932.
Homestake Silver Ltd. optioned the property in 1965. Ore reserves at that time were estimated at 104,325 tonnes averaging 548.6 grams per tonne silver, 2.96 per cent lead, 3.17 per cent zinc. (Northern Miner, September 23, 1965).
In 1966 a drift was driven on what appears to be the main vein, from a point 488 metres from the portal of the 5,880 crosscut, to a point 262 metres north of the crosscut. In 1967 the drift was advanced 558 metres, the drift face being 1382 metres from the portal. This work exposed 5 mineral zones aggregating 91.4 metres of strike length on a fissure which is about on the projection of the Florence-Aspen vein system. Average width (1 metre) and grade of mineralization for the 5 zones was reported at 358.9 grams per tonne silver, 2.76 per cent lead, and 3.67 per cent zinc. The most northerly mineralized shoot was exposed for a vertical distance of 25.3 metres by 30.5 metres of raise.
Pyramid Mining Co. Ltd., in October 1967, optioned an interest in the property and provided funds for the later development work.
Molly Gibson Silver Ltd. was incorporated in December 1967 as a private company to acquire the 10 Crown-granted claims. The shares of the company were held by: Homestake Silver Ltd. (49%), Cominco Ltd. (34%), and Pyramid Mining Co. Ltd. (17%).
