Posted by Ryan Gibb on December 20, 2003
Where it originally came from....(really)
When panning for gold, there were only so many particles they could remove by swirling their pans to extract the larger foreign objects. They then added mercury to what they had left in their pan. Mercury was attracted to the gold, clung to it, and made it float to the top. They would then skim this floating mixture off into a separate pan. On a long pole, they would attach this pan, hold it over a fire, and poof, the mercury would quickly burn off with a flash and cloud of smoke. Leaving just the gold in the pan. Hence the cliche....flash in the pan!