Massive share price fluctuations are just a reflection of impulsive market sentiment on announcements especially when some share traders hop in to make (or lose a quick buck).
The volume says it all, when the dust settles and the volume normalises then you will get a clearer picture of market sentiment and the direction of share price.
I think it's interesting that media report CLZ volume and price as positive yet fail to mention that it's still down 76% after consolidation not that long ago (a trait of a true gambler ) !

Obviously if you are just a day trader or opportunistic trader it doesn't matter for a quick trade.
I used to day trade a lot and the first thing I would do each morning is scan the volumes at pre-trade open with matching announcements! You wouldn't even look at the history of the company as some trades would just be for a few minutes in and then out!
I'd be interested in hearing from any new holders to see what due diligence they did if intending to hold long?