Wash trading for higher volumes to attract attention is my guess.
If we were still under stinc control I'd almost guarantee it.
And, yes, all markets are rigged, for now.
With leveraged trading occurring on the exchanges I don't see how they can't be.
That is how they control the market with the other commodities.
Maybe preparing the ground for march?
Attention might be the right answer.
Guess we'll have to see.