Work within 1911, was continuously being operated by the Canadian Sulphur Ore Company on its Queensboro Pyrite Mine Site in Madoc Township. Expansions at this time had continue to progress when the main-shaft was sunk from the 75-foot level to a depth of 180 feet. Much of the development work at this time was also considered to have been suspended within the main shaft workings. Another shaft at this time was rather situated at a distance of 400 feet from the main shaft and had reached a depth of 100-feet. It was at this time when an opening was made on the 100-foot horizon and had been opened up by drifts running 25 feet to the east, and 80 feet to the west. The No. 2 Prospect shaft was also sunk on the ore-body that was being progressed to developing this section by open-cut methods. Other projects were also on the go when the Canadian Sulphur Ore Company had plans in developing an aerial tramway that was extended from this mine to the railway at a distance of two miles.
Construction within 1912, was progressing when a railway tramway line was extended 2 ½ miles in length from the mine site to the Bay of Quinte Railway Line. Other development projects within this time period were also aimed at constructing a powerline from Madoc to the Mine Site. Power to the mine site was also additionally purchased by the Seymour Power and Electric Company. A plant at this time was also upgrade that consisted of a compressor with 730 cubic feet of air per minute that was driven by a 150-H.P motor and single Drum Hoists at the No. 3 and No. 4 Pits. Development at this time was mainly focus on progressing with the No. 3 and 4 workings. The No. 3 Shaft at this time was also 120-feet deep and became opened up by drifts driven 50 feet east and 50 feet west on the ore-body. Within this time period the No. 3 Open Pit was also being developed by side the No. 3 Shaft that was 75 feet 75-feet deep, 58 feet long, and 25-feet wide. Development confined to the No. 4 Pit was also taken place to the west of the No. 3 and had been 60-feet deep, 25-feet long, and 25 feet long.
Development of the Bay of Quinte Branch was officially completed by 1913, and mining operations were continuous throughout the year. Development work at this time had mainly been confined to the No. 3 Shaft when the No. 1 and 2 Shaft were abandoned at this point of operating. Shaft sinking at this time had continued to progress when the No. 3 Shaft was sunk from a depth of 100-feet to the 150-foot horizon. Lateral development at this time had been confined to extending the West Drift and a raise was put through to the No. 3 Open Pit. A drift at this time would also be driven in order to connect the No. 3 and No. 4 Pits. Preparations at this time had also fitted the shaft with guides in order to install a cage that would also replace the old air driven hoist with a new electrically driven hoist. The company at this time was also under the direct ownership of Mr. A. Longwell and the Vice-President of this company was Mr. Geo. H. Gillespie.
Mining operations would continued to operate a much large scales when underground development was increased in 1914. With the increase of development this had also achieved much higher production of pyrite that was mined for its rich sulphur content at this time. Work at this time was also confined to sinking the No. 3 Shaft that was now reaching a total depth of 200 feet with sinking still in progress. Lateral development at this time was focus on extending the west drift by 200-feet and the East Drift was also continued for 250-feet. A new level would also be cut and station on the 200-foot level that was opened up by a West Drift for 130 feet and an East Drift was driven 200 feet.
Development work during 1915, was confined to sinking the No. 3 Shaft to a depth of 307-feet below the surface. Mining operations at this time were also being confined to the East and West Ore-bodies that were continuously being operated since 1912. Additions at this time were also made to the plant that had underwent new installations when a Marsh and Henthorn Hoist was added for handling cars on the incline from the Crusher Bins to the Railway for shipment. Plans at this time were also made towards installing a 7-drill compressor for the propose development work.
Much of the development work during 1916, was confined to further sinking the No. 3 Shaft that had reach a depth of 350-feet. Lateral development was mainly focus on extending the main drift on the third level by 280 feet and had been directly under the surface showing of the No. 5 Ore-Body Plans at this time were aimed at dewatering the No. 2 Shaft in order to sink it to a depth of 200-feet and connect it with the No. 3 Shaft. With the new expansion underway, it was at this time when the plant was enlarge to occupy a second compressor in order to provide sufficient power for all development. Plans at this time were also made towards purchasing a switching engine in order to handle cars between the mine and the main line of the Canadian Northern Railway.
Development work at this time period of operating was progressed towards sinking the No. 3 Shaft to a depth of 400-feet below the surface. Projections during 1917, had confirmed that the development of sinking the No. 3 Shaft would be additionally continued to a depth of 500-feet below the surface. Work at this time was confined to exending the 400-foot level by drifts that were driven east and west on the ore-body. Production at this time was also focus on developing large size ore-bodies that were developed in the No. 2 and 3 Shaft Operations. Connections at this time had also been made towards connecting the No. 2 Shaft with the No. 3 Shaft by a winze that was collared on the 200-foot level, and a raise was driven in order to connect these two workings. The Canadian Sulphur Ore Company was also still being directed by Alex Longwell as president and Mr. Geo. H. Gillespie was the vice president for the this company. Management at this time was also under the direction of H. F. Smeaton, who had employed 80 men towards this operation.
The Canadian Sulphur Ore Company had continued to sink the No. 3 Shaft to even greater depths of 460 feet in 1918. It was by March, 11, 1918, when the West Drift was opened up by 90 feet of drifting and the East Drift was 64 feet. Development and stoping was mainly confined to production between the second and third level workings of No. 2 and 3 Shaft operations.
Work in 1919, was confined to mining the ore within the Queensboro Pyrite Mine with a workforce of 80 men who were employed. It was also at this time when the No. 3 Shaft was continued to greater depths of 540 feet below the surface. This development at the time had resulted in driving a raise from the No. 3 Shaft to the No. 2 Shaft operation. Production was confined to stoping out ore between the second and third levels, and between the fifth, and sixth levels. Ore within this time period operating was taken by railway to Hamilton, Ontario, for further processing.
Pyrite within the Queensboro Mine is known to occur in massive lenses along the contact between rusty schist to the south and rusty quartzite to the north. Some pyrtic black slate is also present within this formation. Pyrite within the No. 3 and 4 Pits is known to occur in lenses that are known to be up to 25 feet wide. Much of the pyrite within the Queensboro Mine is known to also be distributed in two grades, the frist of these is the low grade siliceous, that’s distinctly banded pyrite containing 35% Sulphur. Ore from the low grade pyrite is known to also pass through quartzite at times in short distances. Most of the high-grade ore within this property is known to consist of faintly banded pyrite that contains 46% to 49% Sulphur. Some of the richest ore that was mined from the Queensboro Mine depends of the natur of the country rock. Pyrite within the adjacent rocks is also known to commonly be fractured in all directions, with the fractures being filled with small veinlets of quartz, calcite, and crystallized pyrites. Most of the pyrite in this formation is known to have been brecciated and the deposit consists of large angular pieces of pyrite, slate, and quartzite that’s cemented quartz, calcite and secondary pyrite. In some sections its also revealed that a small amount of Pyrrhotite and chalcopyrite is also present within this formation.
Pyrite mineralization within the Queensboro Mine is known to be capped by a gossan zone which outcrops in an area 170 m long by 70 m wide, which trends in a general east-west direction which steeply dips to the south. Its commonly known to also range in depths of 0.5 to 10 m and is fragmental in places, with some large subangular massive pyrite fragments supported in quartz limonite matrix. Surface exposure of the gossan zone has since been largely covered with mine waste.