The rock is composed of several layers with slight variations in grain size, color, and appearance. We carefully select the stone to ensure uniformity in tone, highlighting the natural beauty of the material. Occasionally, some tiles may exhibit yellow spots, typically limited to a small percentage of the batch. If yellowing occurs after installation, it can be remedied by gently grinding the affected tiles with a grinder and pads; chemical cleaning is not effective for this purpose. The stone is resistant to both alkali and acid materials, making it suitable for use in both chlorine and salt-water pools. Selected stones do not contain iron-sulfides, thus eliminating concerns about rusting.