The northern portion of the property was originally explored and developed for its asbestos potential by Johns Manville Canada Inc. from the 1950s to the 1970s. During that period, many serpentinite zones in the region were evaluated for their asbestos mineralization potential. In 1947 the first reported work in the immediate area of the ultramafics was carried out by Pen-Star and Pen-More Syndicates and consisted of geophysical and geological work carried out as a guide to prospecting for sulphide deposits. In 1950, asbestos was discovered by J.C. Bromley while prospecting. The property was acquired by Johns Manville in 1951, wherein an exploration program commenced that continued for over 20 years, consisting of geological mapping, magnetic and electromagnetic surveys, and diamond drilling. This work was centred on the Reeves Mine but covered a number of other asbestos showings in the area.
The talc carbonate mineralization of the Penhorwood ore body was defined in 1973, and Johns Manville operated the Penhorwood talc mine and flotation plant from 1974 to 1976, at which time a decision was made to cease operations. Steetley PLC bought and resumed operations in 1978 through to 1988, at which time Luzenac Inc., then an indirect subsidiary of Rio Tinto plc, acquired the mine as part of its North American expansion strategy.
Gold was initially discovered in1998, in core holes which were drilled for development of the Penhorwood talc mine. Visible gold was seen, but not brought to the attention of Rio Tinto management until 2001.
The gold price in 1998 ranged from US $273 to US $313 but rose to a high of US $833 at the end of 2007.
In 2008 Rio Tinto conducted a seven hole drill program, testing the northerly extension.
This program was 1,305 m in total, to a max depth of 150 m with spacing of 50 to 100 m
More significant intersections in these holes included;
22.1 gpt Au over 0.30 m,
9.96 gpt Au over 2.0 m,
13.3 gpt Au over 0.30 m
After assay results from these seven holes Rio Tinto, on the recommendation of its consultants, was able to stake a further 4,760 ha of land.
Rapier's immediate priority is to complete additional drill holes to expand the data developed in the Rio Tinto drilling, this work commenced April 16th, 2013.