Smithsonite, or zinc spar, is zinc carbonate Info Chemical Man

Smithsonite, or zinc spar, is zinc carbonate (ZnCO3), a mineral ore of zinc. Historically, smithsonite was identified with hemimorphite before it was realised that they were two distinct minerals. The two minerals are very similar in appearance and the term calamine has been used for both, leading to some confusion.

How is zinc carbonate formed?
Zinc carbonate can be made by reacting zinc sulfate or any other water soluble zinc(II) salt with sodium carbonate or sodium bicarbonate. It can also be made by the reaction of zincates with carbon dioxide. The resulting precipitate can then be filtered and dried, then stored in an environment free of acidic vapors.

Is zinc carbonate water soluble?
Zinc carbonate is soluble in dilute acids, alkalies and in ammonium salt solutions. It is insoluble in water, ammonia, pyridine, alcohol and acetone. Zinc chloride is very soluble in water, and quite soluble in alcohol and acetone. It is also soluble in hydrochloric acid, glycerol and ether.