The photos below represent my collection of U.S. Mint Philadelphia silver ingots. The two class sizes represented, 5 to 10 oz and 25 oz, can be found in a wide range of thicknesses and weights within the particular class.
The Table at the bottom of the post includes all U.S. Mint Philadelphia silver ingots that I have been able to find through my research to date. Again, I have researched major auction archives including Goldberg, Heritage, Holabird-Kagin and Stack's Bowers which provide information back to the early 2000's. I also obtained information from a number of fellow collectors and dealers, in particular Chris from Old West Gold.
This particular example fascinates me; someone took the time to shave the hallmark off of an ingot that probably was heading for melt!
U.S. Mint Philadelphia silver ingot Table follows: