This is a really interesting summary of Gold Coins, appreciations, well done!
An important one is missing though:

The Pecunio Gold Coin

One Pecunio Gold Coin (PGC) represents exactly 1 gram of segregated, unallocated 999.9 fine gold from LBMA-approved refineries.

Pecunio will exchange physical gold in worldwide branches for tokens available as cryptocurrency on the blockchain.

In times of market turmoil, the PGC token will additionally be used as a tether, but with distinction to existent models of being asset-backed by real gold.

To know more please visit:

https://www.pecun.io