Wyoming Coin Error

I see the " Struck Through Grease" explanation alot but it always has seemed odd to me. Aren't the coins struck with multiple tons of pressure? It just doesn't make sense to me that grease can withstand the tons of pressure used during the process to keep the details from coming through fully. Does that seem strange to others as well? I'm not disputing what coop is saying but was wondering if someone can give further details on it because intuitively it doesn't make sense to me lol.

There is a simple explanation- liquids are not compressible, hence the principle of hydraulics. However, it is not always just grease/oil either. The lubricants can also bind with metal dust to form a hardened "press gunk", it can clog the dies as well and it is the reason why dropped letter errors exist(press gunk clog dislodging from die devices and then being struck into the coin).

Grease, even with all the dust, dirt, metal filings etc that are in it, still acts as a liquid. Liquids, for all practical purposes, are incompressible. So when the coin is struck the grease trapped between the dies and the planchet becomes the "immovable object". It fills the cavity in the die and can't get out because field of the die pressed against the planchet forms a tight seal. And since the grease can't be compressed the metal of the planchet can't enter the cavity in the die. So after the strike you have a blank area on the coin. The faint lettering you see on the OP coin is because there wasn't enough grease to completely fill the letter.