silver standard

When America had a gold or silver standard, the federal budget ran an...

Half income is said to be the "silver standard."

What about a “silver standard” or a basket of metals?

Panic of 1873 resulted in national governments’ embrace of protectionist policies and a shift away from the global silver standard.

Its contribution to metaphor alone is legion — who would want a therapy that is, let us say, the silver standard?