The Silverado property, presently incorporated into a 99- claim group which also includes the Porter Idaho and Prosperity mines, is southeast of Stewart on the slope of Mount Rainey.
The original Rainier Fraction (Lot4511) claim located in 1904 was first part of the Hector Group owned by Chambers, Deaville & Co., who initiated development of the property with several open cuts and some stripping.
In 1920 the Silverado group of five claims was relocated on the Hector ground by J. W. Stewart and John Haahti, of Stewart, who traced a vein at 3,500 feet elevation for 300 to 400 feet and sampled pyritic quartz-tetrahedrite mineralization which assayed 360 ounces of silver per ton and $10 gold.
The Silverado Mining Company was formed in 1921 and controlled by J. J. Coughlan, of Vancouver. During the year, 5 miles of trail was built from the river to the upper camp at 3,850 feet elevation and a camp and aerial-train terminal constructed at 1,700 feet elevation.
A two-bucket single-cable tramline 1 mile long was built to the upper camp and 7 tons of rich silver ore was transported to the beach. By the end of 1927, several hundreds of feet of drifting and trenching had been completed on the series of flat-lying silver-quartz veins on the Silverado ground without much success, but a new set of steep northwest-trending veins outcropping above 3,500 feet elevation at the toe of Silverado Glacier was then discovered in sub-parallel shears, which gave some encouragement to the developers.
In 1928 the control of the 19 Crown-granted claims was secured by the Premier Gold Mining Company and development of the new vein system was commenced by the newly organized Silverado Consolidated Mines, Ltd.
Most of the underground development, which included about 4,000 feet of crosscutting, drifting, and raising on veins, was completed in 1929 and in June, 1930, the Premier Gold Mining Co. Ltd. suspended operations on the property, presumably as a result of the falling price of silver.
In 1932, John Haahti, of Stewart, leased the property and mined about 134 tons from the upper tunnel at 3,688 feet and the veins at 3,750 feet just below the glacier toe. This was mainly massive galena with ruby silver and the ore was hand-cobbed at the
lower tunnel, sacked, and taken by pack horse to Stewart. The lower workings on the canyon vein at 1,860 feet elevation on the Rainier Fraction were explored in 1939 by John Stewart, but no ore was shipped.
The Big Four Silver Mines Limited took over control of the Silverado, Prosperity, and Porter Idaho properties, which included about 30 Crown-granted and fractional claims and attempted to reopen the Silverado in 1946.