Mustard, Stoneware mortar and acacia wood pestle. Add flavour to your food with freshly ground herbs and spices. The stoneware will not absorb flavour or colour from your spices. The interior glaze makes the bowl easy to wash. The bowl is oven, microwave and dishwasher safe. Please note that the wooden pestle should not be washed in a dishwasher or used in an oven or microwave.