The lower two members of the Kunga Group, consisting of the Upper Triassic Sadler and Peril formations, represent the main limestone resource of the Queen Charlotte Islands, particularly the basal massive grey limestone comprising the Sadler Formation. Its thickness varies from less than 30 metres to more than 200 metres.

The Kunga Group, consisting of the limestone members and an overlying argillite member, rests conformably on the Karmutsen Formation, and may be overlain conformably by the Jurassic Maude Group or disconformably by the Middle Jurassic Yakoun Group.

A narrow band of limestone trends west-northwest from Mosquito Lake to Skidegate Channel. The beds dip 50 to 70 degrees to the north. A sample assayed 17.94 per cent CaO, 1.07 per cent MgO, 54.75 per cent SiO2 and 14.96 per cent loss on ignition (Paulsen, 1982, page 3-8).

This occurrence was briefly evaluated by Consolidated Cinola Mines in 1982 as a source of neutralizing medium for the Specogna epithermal gold prospect (103F 034).