Blade's Mastermind, Equivalent to #1500 I purchased this for sharpening knives, starting with #1000, but I'm selling it because I don't use it. There are some grinding particles attached, but they will float to the surface if you soak it in water for about 20 minutes. A ceramic blue-medium whetstone, capable of precision sharpening. - Model: K107 - Color: Blue-Medium - Material: Ceramic - Country of Manufacture: Japan Thank you for looking.