Bathurst-Newcastle

BATHURST-NEWCASTLE (EN: Bathurst-Newcastle; RU: Батерст-Ньюкасл) is the unique in scale polymetallic ore region within the northern part of the New Brunswick province, Canada.

It includes more than 20 pyrite-polymetallic deposits. There have been discovered as the first (1952) the Brunswick-12 (Anakon-Ledridge), and Brunswick-6 deposits, later there have been identified the Keymet, Anaconda (Caribou) Nigadu, Wedge, Heath Steele, and other deposits of various scale. The deposits are confined to the large (68x48 kilometres) dome-like uplift, which is formed by the Ordovician - Silurian volcanogenic-sedimentary rocks, which have been transformed by metamorphism into the quartz-feldspathic porphyrites, chloritic schists and quartzites.

The forming of the ores proceeded synchronously with sedimentation. The largest deposits are situated both on the boundary, and directly above the packs of the volcanic rocks within the sedimentary depositions. The ore bodies of the tabular, ribbon, and lenticular form lay conformably with the country rocks, associating with the ash tuffs and brecciated felsitic lavas. The lower horizons of the ore depositions are formed by the massive pyrrhotite-chalcopyritic, alternating up the cross section, banded sphalerite-galena-pyritic ores; at the tops of the depositions, the ores are fine-grained, prevalently of the pyritic composition. The length of the ore bodies along the strike is 300-400 metres, sometimes reaches 1300 metres, the thickness is from 2-3 to 70 metres. The total reserves (1981) of the metals at all the deposits within the region are estimated at more than 5 million tonnes of Pb, and 12 million tonnes of Zn, with the following content of the elements within the ores at the different deposits, Pb is 1.6-3.8%, Zn is 4.1-9.2%, Cu is 0.3-1.1%, Ag is 36-96.4 grams per tonne, Au is up to 1 gram per tonne.

The largest deposits of the region are the Brunswick-12 (the reserves of the ore are 100.5 million tonnes, where the content of Pb is 3.7%, Zn is 9.2%, Cu is 0.3%), and the Brunswick-6 (the reserves of the ore are 12.8 million tonnes, where the content of Pb is 0.45%, Zn is 1.3%, Cu is 1.1%). The deposits are being developed by the open pit (open pit mine) and underground (two underground mines) methods by the "Brunswick Mining and Smelting Corp." company. The productive capacity of the open pit mine is 1350 tonnes of the ore per day, its depth is 170 metres. The productive capacity of the underground mines is 6.6 and 10 thousand tonnes per day, the depth is 557 and 1480 metres respectively. The annual extraction of the ore within the Bathurst-Newcastle region is 3.6 million tonnes (1981). There is provided the method for the mechanization of the excavation of the layers with the filling of the goaf space. There has been headed the spiral slope from the horizon of 930 metres onto the lower one. The first stage of the crushing of the ore is within the jaw crushers with vibrating feeders, which are installed at the horizons of 500 and 982 metres. The additional grinding and processing of the ore are performed at the beneficiation plant.