WHERE is your GOLD? (If you have a paper bullion bank bill in your hand)?

What would it mean to have a paper bullion bank bill
that can be authenticated?
If the bank bill contains 10 grams of 99.99% gold, and
it is exchanged for a 99.99% gold round weighing 10
grams then the trade is even.
The trade is the same as if the bank bill holder put
the bill in a crucible and burned off the paper or
plastic leaving a gold bead at the bottom of the
crucible.
But, the owner’s house would not be full of smoke from
the burned off paper/plastic substrate. So, the trade
in the bank is cleaner, but it’s the same thing —
your 10 grams of gold is first in the bill, then in
your hand as a piece of yellow metal. If you have a
paper bullion bank bill, you have your Gold in your
hand. You can use the bank to get a quick gold round.
But you need not rely on the bank. A simple crucible is
all you need to obtain your metallic gold bead.
But a bank could also provide paper money, or credit