With durable abrasive particles linked with high-strength bonds, these traditional Arkansas oil stones cut at moderate speed. They also wear slowly, requiring only periodic lapping to expose fresh abrasive particles as much as to restore flatness. Cut from flawless natural novaculite in Pearcy, Arkansas, the stones are described in "grades" rather than grits, since the size of the particles ranges consistently from about 3µ to 5µ. The difference between grades is a matter of particle density; the more tightly packed they are, the finer the abrasive action.