Price goes down when supply exceeds demand.
I’ve seen Roman coins for sale for much less than $50.
If all these coins are suddenly dumped on the market, on which there is already a good supply, I’d expect a very steep drop in price.................
It will probably take years before any of these coins come to market. There are literally thousands of different types even for a single emperor. There are over 3,400 different coins listed in ERIC II (encyclopedia of Roman coins) for Constantine the Great alone. Some rarer bronze types from the period of this Spanish hoard can sell for well over a thousand dollars, so the $50 per coin estimate is just an average. I think the discovery of this hoard will generate much interest among collectors from around the world. Everyone (including me) will want a piece of the action.