First example using US equities, a simple glance shows it all. This is not a breakout analysis, its a momentum analysis. I’d take a step back and wait for the bigger picture.

Two easy observations:

1- Expanding volume often indicated volatility and downward price movement.

2- Contracting volume often indicated low-volatility and upwards price movement.

Edit: adding GDX

Last thought: This doesn’t say volume can’t spike up on down days creating a crash… I’d wait until month close to remove most doubt about this price action being a breakout or not.