PROPERTIES OF HEMATITE
Chemical Formula: Fe2O3 (Iron Oxide)
Class/Group: Oxides and Hydroxides: Spinel
Appearance: Black, gray to silver gray, brown to reddish brown, red, sometimes iridescent, opaque, metallic, known for red to reddish brown streaks.
Characteristics: Is paramagnetic, very brittle.
Hardness: 5.5 – 6.5
Specific Gravity: 4.9 – 5.3 (typical of metallic minerals)
Crystal Forms: Hexagonal, although occasionally scalenohedral and rhombohedral occur. Crystals occur in thin plates and splinters.
Often Found With: Albite, Barite, Biotite, Calcite, Magnesite, Magnetite, Pyrite, Quartz
Varieties: lodestone (large and magnetic), titano (titanium rich), chrome (chromium rich)
Craigmont Mines Ltd. was a very successful copper producer in south central British Columbia (10 kilometers west of Merritt, BC) over the period 1962 – 1982. Copper production was ceased in 1982 as a result of low copper prices, and the shares of Craigmont Mines Ltd. were acquired by the Craigmont Mines Joint Ventures (Craigmont Mines) in 1985. During the period 1985 to 1992, Craigmont Mines supplied media grade magnetite to the western Canadian coal industry from stockpiles acquired when Craigmont Mines Ltd. was purchased. In 1993 Craigmont Mines commenced the recovery of magnetite from the mill tailings deposit created during the copper production operations of Craigmont Mines Ltd. Since the commencement of that operation, Craigmont Mines has produced in excess of 600,000 tonnes of media grade magnetite product. Approximately 450,000 tonnes of proven reserves are present in the remaining unmined tailings deposit.
The current operation consists of mining tailings from the old tailings pile, extracting magnetite from those tailings by means of magnetic separators, grinding the extracted magnetite to meet customer sizing specifications, and re-depositing the material from which the magnetite has been extracted as new tailings. There are no chemical or other additives used in the process. Craigmont Mines magnetite recovery operations are planned to be carried out during non-freezing weather, to the maximum extent possible.
Following the initial mining operation, which consists of bulldozing the tailings into a dozer trap and conveying to a trommel, the tailings are converted to a slurry by mixing with water, and all subsequent operations are conducted with material in slurry form. The water used in the magnetite recover process is maintained in a closed circuit, so that there is no surface discharge from the operation. Make-up water is required to replace water trapped in the newly-deposited tailings and water lost to sub-surface drainage and to evaporation from the tailings pond. Make-up water to maintain the necessary water volume in the system is provided from the Nicola River, from one on-site well, and from drainage from the old adit.