Znucalite or CaZn₁₁(UO₂)(CO₃)₃(OH)₂₀·4(H₂O) is a rare, radioactive, white to pale cream colored uranium-containing carbonate mineral, hydrated calcium zinc uranyl carbonate hydroxide. Znucalite crystallizes in the orthorhombic system, often forming aggregates or crusts, and is found as a rare secondary species in carbonate-hosted (meaning it is mined from carbonate containing formations such as

limestone Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms wh ...

) polymetallic veins, and nearby oxidizing uranium veins; on dump material and coating mine walls, apparently of post-mine origin. It fluoresces yellow-green under UV light. It was first described in 1989, after being discovered in Lill Mine, Černojamské deposit (Black pits deposit) in the Czech Republic. It was named in 1990 by Petr Ondruš, František Veselovský, and R. Rybka for its constituent elements.

References

{{Reflist Carbonate minerals Triclinic minerals