the perfect mug for soups and hot or cold beverages. organic reactive speckle glazed stoneware is a new way to set the table. crafted by skilled artisans, the timeless beauty of the speckled glaze is created from the reaction of the clay and glazes to the fire in the kiln. each piece is subtly different â?? no two are alike. durable stoneware. dishwasher and microwave safe, may get hot in the microwave.