Formula: CeSr(CO3)2(OH)·H2O/(Ce,Ca,Sr)CO3(OH,H2O)
Ancylite-(Ce) and calcioancylite-(Ce) are two common species at Mont Saint Hilaire. They occur in the same mineralogical environments, and can occur together, and are essentially identical in appearance. Without analysis, you can’t be sure which species is present, and possibly both! It occurs as prismatic crystals, or as spherical groups. It can also form as pseudomorphs after other minerals.
