Greek Silver Coin Weight 14 Gram - 100% Fake?

It looks to good to be true, for that age, but I'm no expert.

It looks good, doesn't it? The pictures seem to present an OK coin, but alas, the weight is wrong. I will bet you that if the diameter and thickness are OK, it has a copper core, and is heavily silver coated.

But why, if you are intentionally dishonest, with a fake that appears to be so good, would you bother with a copper core? If you are going to defraud, it would be far easier to pass this piece if it were made from all silver. The cost to make would not be much more, only about $17, which is not much in a $300 coin.

Silver is about 10.5 g/cc, copper 8.93 g/cc. The copper core is 'spot on' for about 85% (14 grammes) of the correct weight.

This is an object lesson to only buy high end ancient coins from a reputable dealer, who knows his stuff. You can also prove provenance, if you wish to sell later on.

I was deliberately nebulous about 'silver coated' to allow for a few alternatives, e.g. dipping a blank in silver metal, or to be electroplated.

Yes, there were a few different weight standards applying across the ancient Greek World. I would need to read up on this subject a bit, before I would comment. I need to read Charles Seltman's book. He did some useful research on the subject of weight standards.