The Speedwell occurrence is situated 1.6 kilometres northeast of the King Tut occurrence (MINFILE 082M 013), approximately 33 kilometres northeast of Chase, 10 kilometres east of Adams Lake and 22 kilometres north of the western end of Shuswap Lake.
The area is underlain by the Lower Cambrian part of the Eagle Bay Formation, consisting of siliceous and graphitic phyllites, phyllitic limestone and greenschist. The metavolcanics and metasediments generally strike northeast and dip 10 to 40 degrees northwest. The rocks are cut by Late Cretaceous or Early Tertiary quartz-feldspar porphyry and mafic dikes with northerly trends.
Mineralization comprises sulphides of silver, lead and zinc within metasedimentary rocks on the north limb of the Nitwikwaia synform. The showings occur within a dominantly metasedimentary succession (EBGs) of siliceous and/or graphitic phyllite, calcareous phyllite, streaky banded calc-silicate rock, limestone and quartzite. The metasediments are stratigraphically underlain by chloritic schists and greenstone (EBG; Preto et al., in preparation).
Mineralized bands near an andesite dike occur across 6 metres within the metasediments. The widest band is 20 centimetres and consists of pyrite, galena and sphalerite.
The Speedwell occurrence is underlain by quartzose schist and phyllite metasediments intruded by hornblende diorite.
The first record of work on the Donnamore property is from 1930. Prospecting was conducted on the Speedwell group in 1930 and 1931. In 1932, several short workings were driven and surface stripping was completed on the Donnamore and Speedwell groups. In 1934, five rock samples collected from the Donnamore claims were sent for analysis. By 1936, two adits (one caved, one locked) had been driven into rusty schists and phyllite on the Speedwell group; additional stripping and a 152-metre-long open cut had been completed on the Donnamore group. In 1936, a 61-centimetre sample collected on the Donnamore claims sampled a band of highly silicified material containing pyrite, galena and sphalerite.
Between 1980 and 1997, much of the Adams plateau area was controlled by Adams Silver Resources. From 1980 to 1992, exploration conducted in the area consisted of geological mapping, soil sampling, air and ground geophysics and 7756 metres of diamond drilling over 150 drillholes along an 8-kilometre strike length.
In 2011, James Thom conducted a reconnaissance exploration program on the Donnamore property on behalf of Intigold Mines Ltd. Exploration focused on new cut blocks and roads exposed on the property between 1997 and 2011. Four chip samples were collected from a road cut near the centre of the property. Two samples, both collected from siliceous shear zones, yielded high-grade assays for gold and zinc.
Of the five samples collected in 1934, three returned significant results. Sample 1, taken across 20.3 centimetres of galena mineralization, returned 1.371 grams per tonne gold, 788.57 grams per tonne silver, 27 per cent lead and 12 per cent zinc; sample 4, taken across 91 centimetres, returned trace gold, 342.857 grams per tonne silver, 15 per cent lead and 8 per cent zinc; and sample 5, taken across 25 centimetres of galena mineralization, returned trace gold, 150.86 grams per tonne silver, 6 per cent lead and 9 per cent zinc (Minister of Mines Annual Report 1934, page D28). In 1936, a 61-centimetre sample collected across a band of highly silicified mineralized rock returned 0.686 gram per tonne gold, 54.85 grams per tonne silver and 22 per cent zinc (Minister of Mines Annual Report 1936, page D43).
Significant results from the 2011 work program included sample Donn1, with 2.5 grams per tonne gold and 0.0149 per cent copper over 0.16 metre, and sample Donn3, with 2.52 grams per tonne gold, 0.247 gram per tonne silver and 0.421 per cent zinc over 0.15 metre (Assessment Report 33011).
