Nero? Interesting, I Say Not Genuine.

I have not seen a nero with his portrait on the obverse and reverse. It is a tetradrachm size coin

Here at CCF people are glad to comment/help. But in the future please spend more time researching before posting, add photos and more information. Make it easier for those who comment. For example I went to Vcoins.com, typed in search line Nero, silver. A lot of coins came up including an example of what I think is the coin you linked with Nero and Claudius from Antioch, Syria. It's a tetradrachm not a denarius in my opinion. You could have contacted the seller, asked them the size and weight to see if it's close to a denarius or the larger tetradrachm. The coin looks legit to me though struck on a small flan and worn. But I'm not an expert.