If the outside of a new purchased internal drive looks worn, could it be an older refurbished drive? Seagate 1.5 tb barracuda.

Just installed a 1.5 tb drive into my G5 mac- I bought it new at Microcenter, but I noticed that the outside of the drive looks worn- the metal is rough- does anyone have this drive and can they tell me what the outside of it looks like. Should the metal on the outside of hard drives be smooth. A bit concerned because there was a firmware issue in the past with this drive and I know many must have been returned. You think Seagate is pulling a switcharoo or do drives look that way. Thanks!