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A structural variant differing in the stacking sequence of closely related layers. zirconolite polytypes can change as substituted-ion size and composition change.

An ordered, anion-deficient fluorite-related structure often written ${\mathrm{A}}_2{\mathrm{B}}_2{\mathrm{O}}_7$. It can accommodate compositions and cation sizes outside the stability range of zirconolite polytypes.

A monoclinic zirconolite polytype with a two-layer repeat. Its zirconium site has sevenfold oxygen coordination.

A monoclinic zirconolite polytype with a four-layer repeat, observed in some actinide-substituted composition ranges.