The rock is built up in several layers, which are slightly different in grain size, colour and appearance. We select the stone ensuring that the whole lot has one tone, showing the natural beauty of natural stone. Occasionally some material with yellow spots may occur, which is limited to a few percent of the lot. Normally it’s only on one side of the tile, if after installation some yellow tiles are visible; the yellow can be removed by grinding them gently using a grinder with pads. Never use chemicals to clean this, as it doesn’t work. Stone is resistant against both alkali and acid materials. Stone is suitable both for chlorine and salt-water pools. As the stone is selected it contains no Iron-Sulfides so rusting is not a problem.