"Rock Tumbler grit", also known as "rock polishing grit", is often a silicon carbide powder that is much harder than the types of rocks that are commonly polished in a very rock tumbler. If it is tumbled inside a barrel with rocks and water the abrasion caused from the grit https://emilianoehhgg.bloggactivo.com/28547462/helping-the-others-realize-the-advantages-of-silicon-carbide-mosfet-drawbacks