Grindstone is a tool used for sharpening
Grindstone may also refer to: A type of millstone used to grind grains such as wheat Grindstone (horse), 1996 Kentucky Derby winner and sire of the racehorse Birdstone Grindstone (album), 2007 album by the Norwegian band Shining Grindstone (time tracking software), a program that allows users to create and organize tasks and to track time Grindstone 100 Miler, a ultramarathon in Virginia Grindstone (video game), a 2019 video game by Capybara Games Places: Grindstone, Pennsylvania Grindstone, South Dakota Grindstone, Manitoba, a peninsula and part of the Hecla-Grindstone Provincial Park in Manitoba, Canada. Grindstone Butte, a summit in South Dakota Grindstone City Historic District in Port Austin Township, Michigan Grindstone Island (Magdalen Islands), an island in the Magdalen Islands, Quebec, Canada Grindstone Island (Ontario), is an island in Big Rideau Lake, Ontario, Canada. Grindstone Island, is one of the Thousand Islands, in the St. Lawrence River in the United States of America.