It was rather in 1917, when a prospector by the name of James Nelson had discovered a quartz vein carrying gold. He additionally had decided to sell this claim off to the Theasaurus Gold Mines, Limited in 1920. It was at this time period when the company owned the Nelson Group of claims on the north boundary of Baden Township, which was at the head of Matachewan Lake. After considerable amount of trenching it was rather reported that an adit was started in 1919, and driven 50 feet, while a three compartment shaft was sunken to a depth of 40 feet. In addition to this development the company also had built two log camps that were both 14 by 16 feet. Company officials at the time had also purchase the much need machinery but it soon became destroyed by a forest fire at Fox Rapids, which was being shipped down the Montreal River. More so the company had also hired a workforce of six miners who became employed under the direction of J.C. Nelson.
1921 - Thesaurus Gold Mines, Limited.
Development on the property had continued from May 10th to November, 1st, 1921. It was rather during this time period when the company had commence development phases of the much needed structures. This whole entire development phase had officially constructed a boiler, and hoist house, and a blacksmith shop. The No. 1 shaft at the time was also being sunken to further depths when it was now reaching 60 feet below the surface. As the mine continued to expand this company had also completed 22 feet of crosscutting at the bottom of this shaft. Almost all the power during this time period was mainly being supplied by a small steam plant.
1922 - Thesaurus Gold Mines, Limited.
Much of the whole entire power plant within this time period had consisted of an upright boiler of 20 H.P, and a 7 by 9 inch Napanee Hoist. Deepening of the shaft had also continued when it was further sunk from the 100 foot level to a depth of 137 feet. This had also resulted in the opening of a second level that became cut on the mines 100 foot level. For the most part this development resulted in crosscuts that became driven 103 feet to the northeast, and 102 feet to the southwest. No other development was reported to have taken place during this time period of operating the mine. Mining operations were reported to have resumed on May 24th to November 21st of that year.
1923 - Thesaurus Gold Mines, Limited.
It was at this time period when the company had place extensive development on the No. 1 shaft as it was now reaching a depth of 300 feet. There was also 100 to 300 feet of lateral development that was establish on the 100, and 300 foot levels. For the most part the shaft is known to follow the vein at an 85 degree angles to the south, and continues to a depth of 41, after which both the vein, and the shaft become vertical. Other statements report that there is a zone that's 200 feet wide, and altered by rusty mica granite, which resembles protogene. In addition to this the zone is known to contain considerable disseminated pyrite, numerous quartz vainlets, and phases resembling quartz porphyry and felsite. Much of the main east-west fracture of where the shaft is sunk is also known to contain white quartz, and a secondary greyish bluish quartz carrying much iron pyrites, some copper pyrites, zinc blende, native gold, chlorite, carbonate, and molybdenum. In several case these minerals are considered to occur as thin seams in the quartz. The Quartz lenses are known to be from 10 to 30 inches in width, and the adjoining granite is highly altered, brecciated, and silicified. Other statements stated that visible gold of fine division was found within the underground workings. Even more company statements had stated that few fault sections were encountered on the 100 foot level drift to the west. There was also a 30 foot dike of diabase of Matachewan Age that intruded this vein to the east of the shaft operation.
The Shields Claims
There was also another claim known as the Shields Claim that had the same line of strike as the Thesaurus Vein. For the most part this vein was rather reported to have been located by W. J. Shields who came upon a vein in a creek bed, Much of this vein system was known for comprising of angular blocks of banded quartz carrying pyrite in a sheared green porphyritic rock.
1935 - Thesaurus Gold Mines, Limited
The company within this time period had officially dewatered the No. 1 shaft, and had commence a small amount of lateral development on the 300 foot level before ceasing mining operations in September.
1937 - Thesaurus Gold Mines, Limited
Operations at the Thesaurus Gold Mine became resumed on January, 1937. It was during this time period when the company completed a total of 207 feet of diamond drilling on the 300 foot level. All other development, and explorations became suspended in February of that same year. No additional work was reported to have been done by this company prior to this.