Throughout aviation history, what airships were metal clad?
At least two all-metal airships are known to have existed, the first one invented by David Schwarz, and test-flown in Tempelhof, in 1897. It flew, but crashed when landing.

Another one, a really successful and better known aircraft, was an American airship, the ZMC-2, that first flew in 1929.

https://en.wikipedia.org/wiki/David_Schwarz_(aviation_inventor)

https://en.wikipedia.org/wiki/ZMC-2