Please note the product you receive may not exactly same as the one shown in the picture because it is made from natural crack-free agate, color and texture of each Mortar and Pestle is unique. Inner Diameter: 50mm (1.97in); Outer Diameter: 60mm (2.36in); Depth: 15mm (0.59in); Mohs’ scale of hardness: 7.2~7.5 Precautions 1. Special care should be taken during use. It is not possible to grind substances with excessive hardness (Harder than Mohs’ scale of hardness: 7.2~7.5) and should not be in contact with hydrofluoric acid. 2. When grinding, the mortar should be placed on an object that is not easy to slide, and the pestle should be kept vertical. 3. When grinding a substance that is corrosive, cover it with a piece of thick paper or plastic sheet, then open a hole in the center, insert the pestle into the mortar, and grind it. The amount of solids must not exceed 1/3 of volume. 4. Large solids can only be crushed and cannot be ground, otherwise the mortar or pestle will be damaged. Explosive materials can only be crushed lightly and cannot be ground. 5. The mortar cannot be heated, and should not be placed in an electric oven to dry. 6. When washing the mortar, it should be rinsed with water first. When a substance that is difficult to wash is attaching on the mortar, a small amount of salt may be added for washing.