A method of preparing a transparent zinc carbonate is disclosed. The method includes dissolving a zinc source in aqueous ammonium carbonate, removing metal impurities from the solution, injecting CO2 into the zinc ammonia carbonate solution, heating a resulting slurry to a temperature of about 100° C. or more until the ammonia is substantially absent from the solution, and drying the resulting zinc carbonate at a temperature from around 150° C. to 300° C. for a length of time that removes water, but retains a significant part of the CO2 content. The ammonia and the carbon dioxide are present in the aqueous solution in a ratio by moles or by weight effective to dissolve the zinc. A nano zinc oxide can be prepared by drying the zinc carbonate at a temperature of 300-400° C. for a length of time sufficient to remove substantially all of the CO2.