The colorful, non-porous surface also makes the bowl resistant from all stains, household acids and alkali solutions as well as easy-to-clean. Create the ideal kitchen experience with the versatility of the DIAMOND collection.. Diamond Silgranit 60/40 Double Bowl Undermount Kitchen Sink - Truffle Made from the rock hard, SILGRANIT patented surface, the DIAMOND kitchen sink features a smooth surface that is resistant to chips, scratches and heats up to 536°F.