The IRON HORSE prospect is located on a southeast trending ridge between Greata and Peachland creeks approximately 11 kilometres northwest of Peachland.
The IRON HORSE occurs in a pendant of limestone, argillite, and andesite of the Triassic-Jurassic Nicola Group which is underlain and intruded by dikes and sills of diorite and granodiorite of the Early Jurassic Pennask Batholith. Contact metamorphic effects are common along the contacts of the Nicola Group pendant; epidote, garnet, pyroxene wollastonite, tremolite, biotite, prehnite, and calcite form skarns containing disseminated and small massive lenses of sulphides. These sulphides include pyrite, chalcopyrite, pyrrhotite, arsenopyrite, sphalerite and molybdenite.
The first recorded work on the IRON HORSE dates from 1936 when the showing was trenched by the Sandburg brothers. In 1956, Noranda Exploration Co. Ltd. is reported to have carried out an SP survey, trenching, and some diamond drilling. In 1966, Brenmac Mines Ltd. carried out geological mapping, soil sampling, an I.P. survey, trenching, test pitting, built 5 miles of road, and drilled 250 metres in 11 short percussion holes and 4 rotary holes. The I.P. survey, which was filed for assessment, showed only a weak, irregular pattern. In 1978, Brican Resources Ltd. staked the property and cut 21 kilometres of survey line. In 1980, Esso Resources Canada Limited funded a magnetometer survey over 24 line kilometres of grid. Magnetic highs were identified which were found to coincide with skarn mineralization. The following year an airborne electromagnetic survey was flown over the entire area; the weak anomalies found in the survey were assumed to be related to an overburden response.
Beginning in 1986 the gold potential of Nicola Group skarns was investigated by Fairfield Minerals Ltd. During the next 2 years Fairfield carried out a major program of soil sampling, prospecting, linecutting, geological mapping, magnetometer surveys, trenching and 6000 metres of reverse circulation drilling. Exploration focused on a number of mineral occurrences within the Nicola Group, including: BOLIVAR WEST (082ENW098), BOLIVAR EAST (082ENW099), BOLIVAR ROAD (082ENW100), BOLIVAR CREEK (082ENW101), CAP (082ENW026) and IRON HORSE.
Prospecting and chip sampling of trenches on the IRON HORSE have identified mineralization with high gold values. Fine visible gold has been identified within marble containing minor disseminated arsenopyrite, and a continuous chip sample across 1.5 metres of garnetite skarn, with 2 per cent arsenopyrite, assayed 15.6 grams per tonne gold (Assessment Report 15834). Other assay results include: 38.3 grams per tonne gold over 1.5 metres in garnet skarn at the footwall contact of a low-angle fault; 15.7 grams per tonne gold across 0.8 metres of an arsenopyrite vein and clay gouge; and 8.2 grams per tonne gold across 2.0 metres of altered diorite with disseminated pyrite and arsenopyrite (Assessment Report 21923).
The 1988 reverse circulation drill program on the IRON HORSE prospect was funded by Placer Dome Inc. and consisted of 3429.38 metres in 25 holes. A grid pattern of holes was laid out to test for mineralized skarn horizons extending from gold-bearing skarn exposed in trenches. The drilling defined a general pattern of alternating zones of skarn and marble cut by diorite dikes and underlain by diorite and granodiorite. The skarn horizons correlated well between drillholes. Bedding in surface exposures indicates a dip slope on the south side of the IRON HORSE ridge. This forms the southern limb of an anticline with the axis plunging 10 degrees to the west along the ridge. Younger hornfelsed volcanics, interbedded with andesite and skarn, were intersected by the drilling on the west side of the grid and confirm the northwest plunge of the anticlinal structure.
Gold assays greater than 0.5 gram per tonne came from 12 holes (Assessment Report 18711). No single lithology was favoured; gold bearing intersections included skarn, marble, diorite and granodiorite, all containing a trace of pyrite. Hole 88-20 assayed 5.8 grams of gold per tonne over 6 metres from 117.4 to 123.6 metres (Assessment Report 18711). Within this intersection a 3-metre section assayed 9.2 grams gold per tonne (Assessment Report 18711). The best assay in hole 88-20, 14.9 grams per tonne gold over 1.52 metres, was associated with pink skarn containing 4 per cent disseminated and massive pyrite (Assessment Report 18711). The maximum values of 6 grab samples collected by the B.C. Geological Survey were: 1 per cent copper, 4.4 per cent arsenic, 19 grams per tonne gold, 13 grams per tonne silver, 0.0150 per cent bismuth, 0.0575 per cent cobalt and 0.0730 per cent zinc (Paper 1989-3, pp.125-126).
An association between sulphides and gold was noted but it was not definitive. Multi-element assays, if carried out, were not reported. Pyrite was the most commonly associated sulphide, usually disseminated in the wallrock. Massive sulphide pods composed of pyrite, pyrrhotite, arsenopyrite and chalcopyrite were intersected but returned low gold values. Gold mineralization was observed to occur mainly near skarn-marble contacts in close proximity to diorite dikes.
