There are many different types of sandblasting sand used for sandblasting applications, and their use varies entirely with the job being performed and the material being sandblasted. The most commonly used type of sandblasting sand is white silica sand. Other materials, such as glass beads, aluminum oxide, silicon carbide and even crushed walnut seeds, are also used for sandblasting applications. Regardless of the material used, however, there are different health hazards associated with each type of sand which must be taken into account during the decision process.
The most commonly used type of sandblasting sand is silica sand. Silica sand is used primarily because it is not only of good quality and durability, but is also usually inexpensive and easily found. Along with those advantages, silica sand can also be reused to a certain extent, unlike some other materials. The primary ingredient in silica sand is quartz, a durable crystal that allows for effective sandblasting. One of the biggest downsides and health hazards of silica sand is that it can create large amounts of dust, which can be harmful when inhaled.
Nearly any type of sand can be used for sandblasting. Sand, however, can consist of other materials outside of silica, which can make certain types of sand exclusive to certain materials. Sands found in tropical regions or along the coastline are generally composed of limestone. Sand consisting of gypsum and obsidian can also be found. A general rule for sandblasting sand is the darker the color, the harder and more effective the sand is.
Beach sand can be used as sandblasting sand. The only problem with using beach sand is that when its from a seaside environment, it will contain salt deposits. Since sand is blasted at incredibly high speeds, sand with salt deposits will often embed salt in the material being blasted. This is very undesirable, especially when sandblasting metals, as it will make metal far more prone to rust and corrosion.
Sandblasting sand is rated by its coarseness, which is measured in particle size and referred to as the "grit." The resulting finish after sandblasting is determined by the grit, with finer grits leaving smoother finishes and coarser grits leaving rough finishes. Other factors besides particle size affect sandblasting and cutting processes, such as the shape of the sand.