The 15 DMA crossed over the 50 DMA just after the Silver sell off. The RSI (Top indicator) was extreamly oversold and eventually corrected itself. (The ratio or any other stock/commodity could not sustain an RSI at the oversold 10 area for long)
The ratio is now in a trading range and may be that way through the summer. Silver led Gold and now the roles are reversed, Gold will lead Silver.
Here is the same chart with Bollinger bands added. The ratio abided by the 'rules' of the Bollinger band on the way down and is now oscillating around the middle section of the band.
For Silver bulls, it's only a matter of time before the ratio is 15:1 again as mentioned by the Coinage act of 1792. Coinage_Act_of_1792