Amorphous crystals are frequently seen in urine from various species. This is a generic and quite non-specific term and just indicates small crystals that are not identifiable as to source. Some could represent fragmentation of larger crystals. The pH of the urine can be a guide as to the likely nature of the amorphous crystals (e.g. amorphous phosphates are more likely in alkaline urine in small animal patients). The main issue with amorphous crystals is that they mimic bacterial cocci (and even undergo brownian movement in urine). When in doubt, perform a gram stain on urine. Amorphous crystals do not take up stain whereas cocci light up blue with gram stain.
