Bill Cust's Bar, located on the Parsnip River 30 kilometres up stream from the Peace River/Finlay River confluence and 50 kilometres northwest of the town of Mackenzie, is now covered by Lake Williston. Gold and platinum placer occurrences found in the Finlay, Parsnip and Peace rivers have been worked since the first discovery by Bill Cust in 1861.

In the 1920's and 1930's, the Ministry of Mines reported that numerous individuals were working the gravels of Parsnip River, recovering fine gold and small amounts of platinum. The placers generally occur in the top 1.5 to 3 metres of reworked glacial gravels deposited in streams and as benches along streams. Normally worked by hand, these placer operations had limited success. The gold is fine and flat and while platinum is common with high values reported locally, it was considered unimportant in most of these placers.

Between 1931 and 1940, 6220 grams of gold were recovered from the Parsnip River (Bulletin 28, page 45). Some iridium values have shown up in assays.