About Us

about Garnet USAGarnet USA, a member of the GMA Garnet Group, located in the historic Ruby Valley, operates a hard rock garnet mining and processing facility that produces large quantities of industrial quality garnet. The various garnet grades produced supply not only the local abrasive markets in the USA but also markets as far away as Europe, Middle East and Australia. The unique high quality garnet crystals contained in the garnet gneiss ore make for a perfect product to use in sand blasting, water jet cutting and other abrasive applications.

Garnet ore is extracted through conventional open pit mining, with the GUSA mine being the first new open pit mine approved in the state of Montana in over three decades. Hard rock in the pit is first blasted then removed to either ore or waste using dump trucks and loaders. The ore is then transported to the processing facility to begin the refinement process. The location and nature of the garnet ore ensures that the environmental impact of mining is minimal.

Wet Processing
Garnet ore is firstly crushed through a series of crushers down to less than 1/8” before being processed through the ‘Wet’ plant. Wet gravity separation equipment, including spirals and hydrosizers, are used to produce a concentrate for further dry processing. At no stage are chemicals used in the process, allowing the water used to be continually recycled as well as there being no risk of contamination to the local waterways.

Dry Processing

Concentrate from the wet process is dried and then processed through the ‘Dry’ plant. A combination of high intensity magnetic separation and mechanical screening results in the various garnet products that are available. These end products are finally packaged into bulk or paper bags up to 4,400lb lots to be trucked to the end users.