According to the patch notes:
That means at Floor 100 and up, Calcite will never drop. At Floor 200, Angelite will never drop. 300, Quartz. 400 Diamond and 500 Larimar. You can still buy from the shop though, but what you get is random. Or just salvage higher tier Crystals/Mythstones. Quartz and Angelite are rarely used, so you can salvage them to calcite. Kyanites are rarely used too, so best salvage them to Larimar or Diamonds for rerolling maps.