Forgeries.
Coins were an invention of the Lydians c.700 BC, over 700 years later than Joseph, and their use spread from there. Had coins been an earlier invention, their earlier use would have been ubiquitous.
(I have a fair acquaintance with numismatics.)
see post 5
I don’t know much about the history of coinage, but since the source of the article is an Egyptian newspaper, and there doesn’t seem to be any independant verification, it does make me wary.
Even if this is legitimate, I have a couple doubts. The article says the coins bear dates when they were minted. Dates according to what calendar? For all we know they could say “3rd year of the reign of Pharoah XXX”, which would not necessarily give us a reliable date on our modern calendars, or a reliable correlation to Biblical events. Also, they interpret a coin with a picture of a cow to represent Pharoah’s dream of the 7 fat cows and 7 lean cows. Now, if the coin had a bunch of cows on it, maybe I can see that interpretation. But for a single “cow”, I think anyone with a basic familiarity with ancient Egypt would probably think it more likely to represent the Apis Bull (Golden Calf), which is a very common motif.
I’m aware historians have long claimed that the ancient Lydians invented coinage (I also used to collect coins, although I suspect not as studiously as you), based on the fact that (i) that’s what the Ancient Greeks believed and (ii) the oldest gold and silver coins that have been found were from ancient Lydia. However, isn’t it possible that the Greeks did not know about Egyptian coins, and that modern scholars did not recognize Egyptian coins as such because they assumed that they must have been something else?
As for use of coins becoming widespread had the ancient Egyptians invented them, that wouldn’t necessarily be the case. I’m sure that there were lots of things developed by the ancient Egyptians that surrounding cultures never adopted (mummification comes to mind), and the same could be true for coins, especially if the Egyptians themselves abandoned their use a few decades or centuries after they invented them. If that was the case, then the Lydians would have “invented” coinage just as much as if the Egyptians had never minted coins, since the Lydians would have developed the idea without any influence from the Egyptians.
Think of our own use of paper currency—we used it during the Revolutionary period, abandoned it, and didn’t bring it back until the Civil War. Couldn’t the ancient Egyptians have used coins during a period of scarcity (when there wasn’t enough grain or whatever to be bartered) and then their use eventually fell out of favor? It’s certainly possible.
Or you’re correct and they’re forgeries. But if they are, how would you explain the existence of hundreds of similar ancient coin-like objects in Egyptian museums (assuming that the article is correct about that)? Surely those wouldn;t all be forgeries as well.