Aes Grave, Too Heavy?

I've never really looked into these - even in this condition (good detail, but stripped of its patina), it is still a very valuable piece and I don't expect I'll ever come across one in my price range. It is a hard thing to tell if it is authentic because it was cast to begin with. I think the clincher might be those corrosion pits - if they form a lip, then the pit wasn't present before casting.

It will take examination in hand to decide if it is authentic. Casting artifacts are much harder to judge when the original coin is cast - that filled 'crack' at the top might be a good indicator on its own.

Previous auction results for this type are in the thousands of dollars, so an expert opinion is definitely needed, probably either an auction specialist or a museum curator. If you're in Europe, your national museum is likely a good place to have this authenticated, but sending it to auction is easier.

I don't think the weight is too strict. The Aes Grave is supposed to be around 270g, but even in the early days the weight fluctuated by a lot just because of how the coin was made. The weight dropped precipitously towards the end of the issue due to metal shortages in the second punic war (links below to examples of various weights in the vast British Museum collection of Aes Graves showing Janus). I don't think it is necessarily possible to pick out a fake by weight alone.

49g: https://www.britishmuseum.org/resea...=list&page=1

62g: https://www.britishmuseum.org/resea...=list&page=1

77g: https://www.britishmuseum.org/resea...janus&page=1

84g: https://www.britishmuseum.org/resea...=list&page=1

90g: https://www.britishmuseum.org/resea...=list&page=1

101g: https://www.britishmuseum.org/resea...janus&page=1

125g: https://www.britishmuseum.org/resea...=list&page=1

132g: https://www.britishmuseum.org/resea...=list&page=1

149g: https://www.britishmuseum.org/resea...=list&page=1

161g: https://www.britishmuseum.org/resea...=list&page=1

218g: https://www.britishmuseum.org/resea...=list&page=1

239g: https://www.britishmuseum.org/resea...=list&page=1

to the community

I agree this would be a rare and valuable coin if genuine. It's difficult to say from a few images. The coin should be examined by and expert in this type. You might want to check out your local museums they be able to help.

You can also send it out to David Sear for certification: https://www.davidrsear.com/

This might also help: http://numismatics.org/crro/results

to the Community!

You could start with a call to Jean Elsen et ses Fils in Brussels. http://www.elsen.eu. They sell ancient coins in their auctions, and I expect might be able to give you an opinion on authenticity, and of course if it is authentic, they could sell it for you (their next auction s iin June)

If not, perhaps they can refer you to another expert in Belgium.