I have a 1851 penny and I have no clue what newcomb means and how I can tell which one it is. Here is the site. http://www.coinfacts.com/large_cent...851_large_cents/1851_large_cent_varieties.htm
What Hobo says Newcomb, Howard R. United States Copper Cents 1816-1857. New York: Stack's, 1944; plus later reprints. The standard classic work on the series. Today, coins of 1816-1857 are attributed by Newcomb numbers. http://www.amazon.com/United-States-Copper-Cents-1816-1857/dp/0880001399 I do not know of a website that may have all of the varieties illustrated. Jim
And to attribute them takes lots of time on the late dates(at least for me). You can go to heritage and search for each variety, but you still need the books to know what to look for. I use two books - the newcomb and grellman book. With the books you will know what to look for on each of the varieties and can then work your way thru them. And on worn or corroded late date large cents it can be impossible at times - just my opinion.
Best thing is the Goldberg Auctions archives. Look for the Dan Holmes collections catalogs I, II, and IV. (Dan Holmes III was his Large Cent Errors) Every single Large cent variety from 1793 to 1857 is pictured except for 1851 N-42 (Unique and Dan couldn't get the owner to sell it to him.) Dan's collection had every variety except 1793 NC-5 and 1851 N-42. The 1793 NC-5 was borrowed from the ANS collection so it could be pictured in the catalog. The pictures are large and clear. Unfortunately you can only see large pictures of one variety at a time and the catalog does not list the diagnostic features for each variety. And for the late dates it doesn't matter if you have the pictures, the fine features that identify the different dies typically will not show in photos. They are good for date placement determination, but if that isn't diagnostic then you are pretty much out of luck. Here is Dan Holmes I http://images.goldbergauctions.com/php/toc_auc.php?site=1&lang=1&sale=54 Here is Dan Holmes II http://images.goldbergauctions.com/php/toc_auc.php?site=1&lang=1&sale=59 And here is Dan Holmes IV http://images.goldbergauctions.com/php/toc_auc.php?site=1&lang=1&sale=62
