Grog (clay) Grog, also known as firesand and chamotte, is a ceramic raw material. It has high percentage of silica and alumina. It can be produced by firing selected fire clays to high temperature before grinding and screening to specific particle sizes. It can also be produced from pitchers.
1 Excellent Support- Every single KURU athletic shoe offers the most supportive design available. Our HEELKRADLâ¢ feature centers the foot to cushion each strike of the heel and absorbs shock with each step.  Durable Construction- Long lasting, dependable shoes will improve your training on any surface.
This makes the shoe more robust, durable and water resistant. It also means the shoe can be completely re-soled if necessary, giving you years of wear out of a single pair. In use since 1869, the Goodyear Welted method is favoured by English manufacturers and copied by shoemakers all over the world.