I found this one from the reject tube. It weighs 7.4g, is not magnetic, and roughly has the size of a quarter.
How do I know if it is not a modern copy?
Not really. That only deals with the US and even then coins made before the '70s didn't need to have copy stamped on them.
What the coin really has going for it is that it isn't on a round flan but instead looks to be an irregular one. This is good.
I really haven't dealt with enough Roman bronzes to really tell if is authentic or not or to attribute it. At least from the photos the inscription looks really weakly struck. But perhaps there is a way to read it?
Roman coins really can look that nice. I would ask on coincommunity.com, they quickly identified some old roman coins my brother had, as well as point out which ones were modern copies.
An expert on coincommunity.com just identified this coin. It's a Roman coin, made between 308 to 309AD.
So it is more than 1700 year's old!!! Now ask me what is my oldest coin that I found?