ALEXANDRIA, Va., Jan. 13 -- United States Patent no. 12,521,835, issued on Jan. 13, was assigned to IDEA VAULT HOLDINGS INC. (Ashland, Ore.).
"Rock tumbling method and apparatus" was invented by Joshua J Gedlick (Ashland, Ore.), Alexander Darin Smith (Ashland, Ore.), Jennifer Ann Hanson (Ashland, Ore.) and Michael Edwin Munter (Ashland, Ore.).
According to the abstract* released by the U.S. Patent & Trademark Office: "After three or four abrasive rock tumbling steps with successively finer and finer adhesive, the rocks are tumbled with pieces of an elastomer, for example plastic foam. The plastic foam may be polyurethane foam. The result is a higher polish than could be achieved by prior abrasive and finishing approaches. A polishing comp...