The story of the Cassiar is largely the story of Thibert Creek. Prospectors had been taking gold from the sands and bars of the Stikine for more than a decade before the strike on Thibert Creek in 1873, but these takings were small and the Cassiar goldfields  still awaited their discoverer – a stranger coming from the far Mackenzie.

In 1869 Henry Thibert left Minnesota with one companion, intending to hunt and trap along the Mackenzie River for a few seasons, then cross Rockies and traverse British Columbia to the coast. His journey was one of hardship and privation. In the spring of 1872, having crossed the Rockies he wintered at a Hudson’s Bay post on the Deloire. There he met up with another explorer by the name of McCullogh, and together they worked their way to Bucks Bar on the Stikine River where they spent the winter.

Heading out in the spring of 1873, Thibert arrived at the mouth of the creek which bears his name. There he found coarse gold on the bedrock, running 2 to 3 ounces to the pan at a depth of only 18 inches.

By August of that year, twenty miners had arrived. News travelled fast and miners from the Cariboo and Omineca left their diggings. By 1874, the population of the district had increased to 1,600, and perhaps as many as 2,000 visited the area. Other streams were prospected and proved to be just as rich as Thibert Creek. Claims on Dease Creek averaged an ounce a day to the man. One company took out 200 ounces in one week, while two men together washed out 50 ounces in a single day.

The pre-glacial creek channel is the source of the placer gold. Remnants of the old channel occur as a number of benches along the present creek channel. The materials filling the channel are sands and gravels with some silt and clay. Very little gold has been found above the mouth of Berry Creek which is located 10 kilometres upstream from the mouth of Thibert Creek.

Bedrock is exposed in the bed of Thibert Creek at only a few places. Platinum is known to occur in the creek. About 68 grams per tonne of concentrate is reported to have been obtained in one hydraulicking operation.

Principal work was done on the lower 16 kilometres of the creek. Much of the early work consisted of drifting and shafts on the benches. Hydraulicking was done by the Thibert Creek Mining Company, and several other companies, during 15 seasons or parts of seasons from 1901 to 1922. Intermittent work was carried out by numerous companies, syndicates and individuals from the time of discovery until about 1937. Thibert Creek produced 1,570,083 grams of gold between 1875 and 1935, the majority of which was mined prior to 1900.