When buying zinc carbonate (mostly basic zinc carbonate in trade), price should not be your only concern. Different batches vary a lot in zinc content, heavy‑metals, particle size and impurities. Picking the wrong grade will mess up your finished goods or cause export compliance issues.
First, figure out your end use. For rubber activation or paint filler, regular industrial‑grade works fine; finer powder gives better dispersion. If you use it for feed, go for feed‑grade with strict heavy‑metal limits and valid certificates. For cosmetics or high‑end synthesis, choose high‑purity material with very low heavy‑metal traces and check REACH documents before ordering.
Always look through the COA report. Pay attention to zinc content, moisture and impurities. High moisture leads to caking during sea shipping. Fine powder brings good activity, while coarser powder suits cost‑focused general production.
For overseas buyers, check batch COA and required compliance papers. Stay away from cheap goods with unclear specs — unstable batches may cause production failures and customs problems. If you have special needs, talk to your supplier first. It’s smart to run small trial orders before placing large bulk purchases.