So you have to have trust that others will have continued trust in the currencies or values that your example currency is pegged to.

Ultimately it seems that any material you treat as a store of value, rather than as a commodity or material that is valuable to you for its own properties, includes this trust that others will value it. If others do not value it, it is not a store of value, its usefulness to you is reduced to its own intrinsic properties rather than the value others place on it.