No known way to get this in the game yet.
Contents
ItemQuantityChanceFor
Refining Stone (Bound) x2100%GuaranteedLevel 1 - 100
Expert's Refining Stone (Bound) x150%One pick from a pool, 50% to rollLevel 1 - 100
Artisan's Refining Stone (Bound) x115%One pick from a pool, 15% to rollLevel 1 - 100
Artisan's Ultimate Refining Stone (Bound) x11%One pick from a pool, 1% to rollLevel 1 - 100
Silentium (Bound) x1-2100%One pick from a poolLevel 1 - 100