The Tom 1 showing is hosted by Early Jurassic monzodiorite to gabbro of the Lehto plutonic suite. Veining and alteration containing hematite, chlorite and vuggy quartz are widely distributed in the Lehto Porphyry. Most of the feldspar porphyry is weakly to moderately sericitized. Several quartz veins a few centimeters thick contain disseminations and blebs of chalcopyrite. Samples of such material contained copper, in two samples at one location, of 0.35 per cent and 1.43 per cent along with 2.2 and 0.8 gram per tonne silver respectively (Samples 26031 and 26032, Figure 4, Assessment Report 21963).
WORK HISTORY
The Tom property was staked in 1988. The first recorded work on the property is that described by Nicholson (Assessment Report 19640) for Ecstall Mining Corp and Omega. Old shovels and lumber on the property, suggesting some work was carried out previously.
In 1989, owners Ecstall Mining and Omega Gold carried out a preliminary program which consisted of a geological examination, rock geochemistry and stream sediment geochemistry (Assessment Report 19640).
In 1990, Santa Marina Gold Ltd had a limited work program conducted that consisted of prospecting, reconnaissance mapping, silt (15) and rock (19) sampling in 1990 (Assessment Report 20804)).
In 1991, Ecstall Mining Corp carried out a three day program to provide a geological assessment of the overall exploration potential of the property (Assessment Report 21963). Most of the property, some 1575 hectares, was covered on foot at a reconnaissance level. Thirty-four rock chip samples were collected and analyzed for copper, lead, zinc, silver and gold as well as varying combinations of other elements.
In 1992, Kennecott Canada Inc collected soil samples at 50 metre intervals across the area interpreted to be the zone of alteration, and two rock samples, taken of a felsic unit encountered in outcrop, were submitted for whole rock analyses (Assessment Report 22572). The Tom claims were owned by Ecstall Mining Corp.
See the nearby Tom 2 occurrence (104B 676) for related geological details.