It turns out that quartz is the only abundant mineral that's piezoelectric, meaning that it generates a charge when it's placed under strain. While you don't need to understand why that's the case ...

In this way, more gold is drawn out from the solution in areas with pre-existing gold grains. “In essence, the quartz acts like a natural battery, with gold as the electrode slowly accumulating ...

“In essence, the quartz acts like a natural battery, with gold as the electrode, slowly accumulating more gold with each seismic event,” Voisey said. Tagged In Earth Electricity ...

The tyrannosaur of the minerals, this gold nugget in quartz weighs more than 70 ounces (2 kilograms). Heritage Auctions. March 17, 2013, 4:07 PM EDT. By Science. By Becky Oskin, OurAmazingPlanet.