Get them all and assemble your copper set These lustrous rounds measure 39 mm in diameter and contain One Avoirdupois (AVDP) Ounce of .999 Fine Copper. mint fresh beautifully struck, one ounce copper rounds. These rounds are an excellent way to buy copper, are easily stacked and stored, and are perfect for investors and collectors alike. When you want to make a solid investment, it's time to buy copper. Buying copper rounds to invest in copper because you know that you are getting freshly minted pure .999 fine copper bullion 1 oz. replica coins, show them off to other collectors and enjoy the pure beauty.