Norton use the term 'India" stone for their Aluminium Oxide stones and 'Crystolon" for their Silicon Carbide stones. This is the standard double sided pre-filled, fine/coarse 2' wide x 8" long oilstone.
Norton use the term 'India" stone for their Aluminium Oxide stones and 'Crystolon" for their Silicon Carbide stones. This is the large double sided fine/coarse, pre-filled oilstone.