Hello everyone! We are under construction with our brand-new, in-ground, gunite pool. I am trying to decide what waterline tile to use. I am looking at the Quartzite tile by National Pool tile. I love the look of the natural stone but I am getting mixed opinions on it's performance. Some say it works great and others say I will have problems with calcium buildup and it looking poor due to water absorption. Have any of you used this Quartzite tile for your waterline? If so, what is your opinion of it? Have you been happy with it or has it caused problems? Thank so much!!