Plunge Protection Team head has recently quit
https://www.zerohedge.com/news/2019-05-28/head-plunge-protection-team-quitting
The gold:silver ration is historically about 16:1 (as in prosperous Roman times). The silver:gold ratio in the ground is about 10:1. The current ratio is ~90:1.
The ratio must be allowed to float freely on a bimetallic standard for the "gold standard" to work correctly. Silver has been used to push a round the gold market and has been suppressed to a higher extent.