The Little Bertha occurrence is situated approximately 600 kilometres east of the Granby River, approximately 22 kilometres northeast of Greenwood.
The Little Bertha property is situated within a belt of Devonian to Permian rocks immediately west of the fault contact with a Proterozoic gneiss complex (Grand Forks Gneiss). The northerly trending Granby River Fault is inferred to be the eastern margin of the Republic Graben, a fault-bounded package of rocks that extends north from Washington State. The Paleozoic rocks consist primarily of greenstone, chert and argillite and limestone of the Knob Hill Group. Undivided sedimentary rocks of the Triassic Brooklyn Formation underlie the area just south of the prospect. Intruding the stratigraphy are granitic plutons of the Jurassic Nelson Batholith and dikes, sills and intrusions of the Eocene Coryell Plutonic Suite, which are syenitic to monzonitic in composition.
The Little Bertha showing consists of one or more north-northeasterly trending, east-dipping quartz veins in dioritic rocks of the Nelson Intrusions. Pyrite, galena and chalcopyrite occur in the quartz gangue. Evidence of faulting is seen in the uppermost Little Bertha workings (stope), where a slickensided fault plane marks the hanging wall of the vein. The vein ranges up to 2 metres in width. The estimated strike length of the vein is approximately 100 metres and is considered open in both directions. Local concentrations of sulphides were noted near the hanging wall contact. Sampling in 1996 yielded values of 26.81 grams per tonne gold, 475.89 grams per tonne silver and approximately 1.5 per cent combined lead and zinc from a selected sample of sulphide-rich vein (Assessment Report 25993).
From 1900 to 1939, 876 tonnes of ore were shipped from the Little Bertha claim. Approximately 83 per cent of this total was mined from 1937 to 1939. From this ore, 13 251 grams of gold, 120 276 grams of silver, 29 kilograms of copper and 391 kilograms of lead were recovered.
The Little Bertha claim, originally owned by A.T. Kendrick, was developed by a 40-foot shaft and 250 feet of tunnelling by 1905. Bertha Consolidated Gold Mining Company Limited, incorporated in February 1907, apparently held the claim for a number of years.
In 1917, a new company, Pathfinder Consolidated Mining Company, was formed to work the Pathfinder (MINFILE 082ESE075) and Little Bertha claims; the Iron Bell and Derby claims were subsequently added to the company holdings. Intermittent work by the company was confined to the Little Bertha claim, where a crosscut adit was begun in 1919; by 1932, the adit had been extended to 300 metres. Leasers worked the Little Bertha claim from 1937 to 1939.
Exploration in the 1960s by Hecla Mining Co. and Alwin Mining Co. consisted of trenching, reopening adits and completing at least 12 diamond drill holes (Alwin). Only passing reference to this work is reported.
In 1980, Aries Resources Inc. optioned the property and conducted exploration around the main workings at Pathfinder, Diamond Hitch and Little Bertha. Three short holes were drilled on the Little Bertha vein zone with limited success. In 1980, Dolmage, Campbell and Associate conducted geological mapping between Pathfinder and Hornet creeks.
Nu-Lady Gold Mines Ltd. optioned the property in 1983. Exploration between 1983 and 1985 focused on the sulphide-rich mineralized zones at Diamond Hitch (1983 to 1984) and Pathfinder (1985) and consisted mainly of shallow diamond drilling. Five of the seven holes drilled on the Diamond Hitch were closely spaced over a 50-metre strike length.
From 1987 to 1988, an exploration program by Ber Resources Ltd. was followed up with magnetic, very low-frequency electromagnetic, soil and geological surveys and further trenching. This work was mainly in the eastern property area on the Pathfinder trend.
Two programs were completed on the property by Niagara Developments in 1992 and 1994. The earlier work consisted of a very low-frequency electromagnetic survey in the Little Bertha area. The latter featured a fairly detailed ground magnetic survey over the eastern Pathfinder trend.
Cassidy Gold Corp. held an option on the Pathfinder property between 1996 and 1999. Much of Cassidy’s exploration effort focused on the area between the Little Bertha and Pathfinder workings. The primary target was high-grade gold (silver)-bearing mesothermal quartz veins similar to the Little Bertha. Massive sulphide and skarn zones were secondary targets. Exploration in 1996 consisted of grid preparation, soil and rock sampling, geological mapping and grid geophysical surveys (magnetic, very low-frequency electromagnetic, induced polarization). Cassidy dropped the option in 1999.
In 2000, Conlon Resources Corp. explored the property through grid preparation, soil geochemical surveying, geological mapping, prospecting and sampling, mainly in the new Pathfinder grid area.
In 2009, the property was examined by Drs. Gerry Ray and Bob Thompson, who suggested a high potential for Rossland-style gold-silver-copper mineralization based on several geological similarities (Press Release, Kingsman Resources Inc., February 17, 2010).
In 2010, Kingsman Resources Inc. released tellurium results for samples from low-grade dumps, rock piles and an erratic float boulder on the property. In the Bertha area, the highest values include sample 90829.12 with 85.79 grams per tonne gold and 315 parts per million tellurium (Press Release, Kingsman Resources Inc., March 12, 2010).