What is a 'Whizzed' Coin? : eBay Guides

a whizzed coin has been buffed or polished to give it the appearance of the luster found on a mint coin. Whizzing is often done to try to sell the coin at a higher grade than it really is. The process is sometimes done by using a fine brush attachment on a high speed drill. Whizzing a coin may hurt the value of it rather than help it because it actually causes wear to the surface of the coin.