Progress report on the Clinton Creek asbestos project

Country rocks in the project area are metamorphic rocks of the Yukon Group whose age, though uncertain, is believed to be late Precambrian and/or early Paleozoic. Several small ultramafic bodies have intruded into these rocks. Almost every serpentinite mass contains chrysotile, but the amount and quality is highly variable.

The ore-bearing, ultramafic body trends northeast in an elongated dome shape. Its upper surface plunges 10° to the southwest beneath graphitic, limy argillites. The ore zone is restricted to the northwest side of the serpentinite body.

Degree of serpentinization and intensity of fracture seem to be the major controlling factors for the formation of chrysotile.