The Chu Chua coal deposits are located in the lower sections of Newhykulston Creek approximately 3 kilometres southeast of Chu Chua and 80 kilometres north of Kamloops. The old minesite is approximately 1 kilometre east of the Canadian National Railway track.
The coal forms thin seams in shales and sandstones of the Eocene Chu Chua Formation, which fills a small successor basin in the North Thompson Valley. The coal-bearing strata in general strike northeast and dip 23 to 25 degrees southeast.
Three main coal seams (low rank bituminous to high rank sub-bituminous), the Gray, Smith and Thomas, occur in the Chu Chua Formation of Middle to Upper Eocene age. The main coal seams are interbedded with sandstone, shale, conglomerate, and a number of thin coal seams. The Thomas seam (stratigraphically highest) has been the location of much of the development in the area. It consists of two benches, the lower (0.76 metre thick) separated by 0 to 3 metres of shale and sandstone from the 0.56 metre thick upper bench. The benches contain many interbeds and partings of shale and sandstone. The Smith seam is a double seam with the benches separated by a grey sandstone. The Gray seam (stratigraphically lowest) is approximately 1.1 metres thick and is underlain and overlain by shale. The coal contains 3.6 to 4.0 per cent moisture, 13.8 to 37.3 per cent ash, 29.4 to 37.9 per cent volatile matter and 29.6 to 44.7 per cent fixed carbon.
The first recorded examination of the deposits was in 1877. Minor production occurred in 1893 by North Thompson Coal Mines. The seams were mined (underground) by the Chu Chua Coal Company, with production from 1920 to 1922 varying from 1 to 2 cars a week to 40 tons per day. The operation was shut down in 1923.