I think 100 # is too much.
I visited a gold mine on Northern Luzon in my younger days. My wife and I just showed up in our bright red volkswagen and they gave us a royal tour. I guess they figured two young Americans showing up un announced in the remote location made up de facto important.
Any way, they took us to the vault and handed my wife an ingot. It was so heavy she nearly dropped it. Had it been 100 # I know she would have.
If you check Kitco, the bar they have is 400 oz or 25 pounds.
The pallets would definitely be ok with these size bars.
Check Kitco.com bullion
The bottom line: Special "things" need "special" pallets.