Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of gold miner Pretium Resources Inc (NYSE:PVG) jumped as much as 97% today before settling in at a 78% gain for the day.

So what: The driver of the outstanding performance was results from gold recovered from a bulk sample taken from Valley of the Kings mine. The company targeted 4,000 ounces of gold from a 10,000 metric ton sample, but there was actually 4,215 ounces in just 8,090 metric tons of rock. 

Now what: The result was about 16 grams of gold per ton versus expectations for 13 grams. This is a huge win for investors because the increased output is levered straight to the bottom line. Commercial production isn't expected until 2016, so there may be a long wait for significant revenue; but this is a huge positive for the company. Keep an eye on future announcements to see if the full sample continues to show the potential of this early report.