Well I heard back from the seller... the coin is in fact 2.83g.. He is 100% sure it is authentic (for whatever that is worth) BUT he did assure me that once coin arrives if I have any doubt whatsoever he will refund me for the coin and any shipping costs. He was very prompt and polite with his reply. So I suppose the next step is to wait for the coin and post a few more pictures when it arrives and go from there. I appreciate all of the responses so far.