Inks Lake is about 1500 metres northwest of Jacko Lake and contains dilute sodium sulphate brines. Andesite of the Upper Triassic Nicola Group underlies the area.
A sample was taken from the lake to determine salts present. The analyses of the brine yielded 2.8 per cent total solids and a specific gravity of 1.027 at 16 degrees Celsius. The composition of the solids is as follows: 60.0 per cent Na2SO4, 31.7 per cent MgSO4, 1.5 per cent NaCl, 3.0 per cent Na2CO3 and 3.7 per cent CaSO4 (Bulletin 4). The sodium sulphate and magnesium sulphate minerals assumed to be present are mirabilite and epsomite, respectively.