I agree that you made a nice purchase! The 1862 IHC is super nice but it is really hard to tell if it in fact has been cleaned without better pics. The 1851 Large Cent definitely appears to have had an old cleaning and polishing but if it is a scarce to very rare variety, it still could worth big bucks, so it is really worth trying to identify (attribute) the variety. There are 42 Newcomb Varieties listed (previously 45 varieties for the 1851 Large Cent but N-11, N-28 and N-32 have been delisted).
Frank