The Poisonmount (Poison Mountain) Creek gold placer, near the confluence of Poisonmount Creek with Churn Creek, is within gravels derived exclusively from sandstone, conglomerate, siltstone and shale of the Lower Cretaceous Jackass Mountain Group and granodiorite to quartz diorite of the Paleocene to Eocene Poison Mountain intrusions. Glacial deposits are absent. The thickness of surficial deposits range from 1 to 6 metres and contains very little clay.

Placer gold occurs in gravels and in bedrock cracks of the present Poisonmount Creek stream bed. The gold particles recovered vary from the size of a pin head up to the size of a grain of wheat; there is little flour gold. The color is generally dark bronze- golden. The gold is generally rough, though on occasion some pieces are well worn and flattened. Most of the gold recovered seems to have travelled only a short distance, and was possibly derived from scattered narrow pyritic quartz veinlets in porphyry dykes related to the Poison Mountain intrusions.

The placer gold was discovered in 1932, and resulted in staking and working along most of Poison Mountain Creek. In 1982, Long Lac Resources Ltd. conducted a bulk sample testing of the stream gravels. Gold values were found to be very low.