The Metex Exchange currently lists 4 different metal backed tokens. These blockchain native tokens can be traded against crypto such as Bitcoin and USDT.
If you would like more details about these tokens please visit here. 

AUS = 1g Gold Token:  Gold Standard managed by Ainslie Wealth
AGS = 1g Silver Token:  Silver Standard managed by Ainslie Wealth
MxPt = 1g Platinum Token:  Managed by Metex Corp
MxPd = 1g Palladium Token:  Managed Metex Corp

Each of these tokens are listed against both Bitcoin and USDT (Tether) trading pairs.

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