Urine crystals (commonly uric scale) are mineral and organic deposits formed when urine salts and uric acid precipitate and bind to surfaces. They appear as hard, yellow-white or brown crusts around drains, weep holes, and trap areas and can cause odors, slow drainage, and blockages.
Additional Tips and Tricks
Natural Alternatives: For minor scaling, distilled white vinegar or citric acid can be used as more gentle, eco-friendly acidic agents. How to get rid of urine odours in urinals? how to dissolve urine crystals in urinals
If you prefer to avoid harsh acids, bio-enzymatic cleaners are an excellent alternative. These contain "good" bacteria that produce enzymes specifically designed to "eat" organic matter and uric salts. How to dissolve urine crystals in urinals (overview)