UNDERSTANDING INDUSTRIAL GARNET
Not all Garnets are naturally equal; then again, not all Garnets are processed equally. These two factors determine the eventual end products sold to customers.
Industrial Garnet Species
There a wide variety of Garnet Species with varying qualities. Some are harder on the MOH scale then others and they all vary in colors and composition. In general, Almandine Garnet is preferred for its hardness and density. At the same time, Rock Garnet is preferred to Alluvial Garnet as Rock Garnet is generally sharper. Rock Garnet generally occurs as a large rock, sometimes forming together with other rocks such as Granite, whereas Alluvial Garnets occur as sand. Alluvial Garnets being sand occurring in rivers or beach have been "weathered and polished" over many many years. Alluvial garnets are pretty to look at, being slightly translucent with rounded edges (due to the years of exposure to the elements and to itself rubbing together). Being rounded, Alluvial Garnets are less effective when used for Abrasive and Cutting purposes. In addition, being already in a sand form, its size is limited to smaller mesh sizes, and therefore its uses are also limited. Rock Garnets on the other hand are sharper due to the fact that during processing, they are crushed to size with bigger rocks, splitting into smaller pieces, thereby forming sharp edges.
Stockpiling Crushed Industrial Rock Garnet
Processing Industrial Garnet
When Processing Rock Garnets, factories choose basically two methods of crushing, Auger Crushing and Knocking Crushing.
AUGER CRUSHED ROCK GARNET
Auger Crushed Garnet is Rounded and Evenly Colored
The first method uses an auger to literally grind down into size the rock garnets. This process creates beautifully formed garnet fines with an even color, whereas due to the grinding effect, the edges of the garnet fines have been rounded off.
KNOCKED CRUSHED ROCK GARNET
Knocked Crushed Garnets have sharp edges but do not have a uniform color
The second method crushes garnet rocks by knocking them together so that they split up into smaller pieces. This method retains sharp edges and creates the best cutting and abrasive industrial garnets.