Vintage Souvenir Advertising. THE CARBORUNDUM COMPANY, MANUFACTURERS OF ABRASIVES, NIAGARA FALLS, NY. U.S.A.

Blue stone inside brown & gold leather case. Slides in at one end. Company name on the stone itself has mostly worn off.

Case measures 3 1/2" x 1 1/2".  Stone measures 3" x 5/8f". For sharpening a knife - or lighting a match?