Yes, and they all need vaulting, with storage and auditors and a centralised choke-point. Again, this is a half-baked application of block-chain. This puts us back to Renaissance Italy with the start of fractional reserves. While gold is gold, this will not change. No amount of examples of cryptified-pm's is going to make this any less true.
I can think of perhaps once exception though where a half baked cryptified precious metal backed block-chain (HBCPMBBC lol) may have great utility. Say if China (being the savvy gold bugs that they are (not letting metal out of the country and what not)) decides to issue a gold crypto. If all the gold is locked in the country, and this gold backed crypto functions as sovereign currency, well then they might just become the global economic hegemony much faster.