Hydromagnesite deposits are being formed today in many of the playas of the Chilcotin Plateau, a region characterised by a semi- arid climate, relatively mature topography and, in some areas, internal drainage systems.
The Big Creek hydromagnesite showing occurs about six kilometres south of the Fletcher Lake showing (092O 084) in the same drainage system as Fletcher lake. It is estimated that about 500 tonnes of hydromagnesite are present with the composition of 64.2 per cent MgCO3, 5.7 per cent CaCO3, 0.60 per cent Al2O3, 1 per cent Fe2O3, 11 per cent water and 16 per cent insoluble material (Bulletin 4).