Honestly, pareho lang sila as calcium supplements pero may slight differences, Calvit Gold usually has added vitamins and minerals na mas complete ang formula, habang plain calcium carbonate ay yung basic form lang ng calcium. Both work, but if you're looking for something with extra nutrients especially during pregnancy or postpartum, Calvit Gold might be better; though I'd ask your OB which one they prefer kasi depende rin sa needs mo at ano na yang other vitamins you're taking.