The Century Limestone occurrence is located on Tlupana Inlet, east of Deserted Lake, approximately 31 kilometres west of Gold River, B.C. It is accessed via the Head Bay Forest Service Road between Gold River and Tahsis.
The area is underlain by sedimentary and volcanic rocks of the Late to Middle Triassic Vancouver Group (Quatsino Limestone and Karmutsen volcanics and Parson’s Bay sediments). These rocks are in fault contact with diorites of the Crystalline Westcoast Complex and all rocks have been intruded, locally, by the Eocene Catface Intrusions.
Locally, the area is dominated by the Upper Triassic Quatsino Limestone. The limestone is generally, massive to thickly bedded and well marbleized. The colour and texture of the limestone are variable from bright white to dark grey, and from fine-grained to coarse-grained, respectively. The Quatsino Formation is moderately dipping at approximately 45 degrees and strikes northwest. Late, fine-grained mafic intrusive dikes of andesite to trachyte cut the limestone but are, generally, spaced greater than 50 metres apart as identified from geophysical surveys.
Sulphide mineralization is isolated and restricted to pods of skarn-style massive sulphide mineralization at or near the contact margins of intrusive bodies but generally the limestone is clear of sulphide mineralization.
From 2005 to 2006, Double Star Resources completed a program of rock geochemistry, ground magnetic surveys and aerial photography. Results of this program indicated that the property hosts a potentially large tonnage limestone deposit of sufficient grade and quality to justify further exploration work.
Average whole rock analyses from 321 samples of limestone in 2005:
---------------------------------------------------------------------------------Si02 Ti02 A1203 Fe203 MnO MgO CaO K2O P205 Ba(F) LOI Total % % % % % % % % % % % % 0.78 0.01 0.11 0.11 0.02 4.3 50.5 0.02 0.01 0.01 43.9 99.70 (Assessment Report 28386) --------------------------------------------------------------------------------- |
Exploration work in 2014 was undertaken for Opus ventures Ltd. to better quantify the variability of the limestone chemistry. Of 10 samples obtained on the Century Limestone area (east area), results are as follows (Assessment Report 35545):
SiO2: average 0.6 per cent; range 0.15 to 2.01 per cent
MgO: average 7.33 per cent; range 0.41 to 19.88 per cent
CaO: average 47.56 per cent; range 32.08 to 55.14 per cent
In 2016 and 2017 Callache Stone Quarries Inc. conducted road access upgrades, bulk sampling and diamond drilling on their Tahsis property, which includes the CENTURY LIMESTONE area.
