Hydromagnesite deposits are being formed today in many of the playas of the Chilcotin Plateau, a region characterized by a semi-arid climate, relatively mature topography and, in some areas, internal drainages systems.

Hydromagnesite of the Gay Lake showing is being deposited within Recent lacustrine sediments within a playa developed on older glacial gravels and Tertiary volcanic rocks. Through evaporation of the water of Gay Lake during the summer, hydromagnesite is being concentrated in the clays of the lake bottom and around its margins.

The deposit is estimated to contain about 100 tonnes of hydromagnesite.