Identifying mix

Question
I have a found dog (that is, I have no idea who his parents are) and I'm trying to figure out his breed.  He's black and his head is definitely labrador-shaped, but he has relatively long hair, even on his head, and his tail is curved and feathered.  His undercoat has reddish tints (he looks maroon in some lights...really cool) and his paws appear to have at least some webbing.  I thought for awhile he might be a Chesapeake, but his hair isn't long enough and his head is clearly labrador.  He's a great dog and I'm really interested in what he's made of.  He's about 75 lbs.

Answer
Sorting out mixes can be tough.  Complicating things is that a male a female was seen mating with may not be the sire of all or any of the puppies she whelps.  I think maybe DNA can now help, but not sure where to send you.  

Check Flat Coated, Curley Coated, and Newfoundland Retrievers.  You can find pictures of them at www.akc.org.