The Crown Jewel (not to be confused with the Crown Jewels of England) was discovered in 1992 by Sonora Mining Corporation Mine in Jamestown, California.
Initially, the workers thought it was a piece of junk metal and were all no doubt offering to take it home for recycling. You know, just protecting the environment and all that.
However, when they examined it further, they found out that it was actually large single piece of crystalline gold. Nevertheless, I'd still have offered to take it home for recycling.
It originally weighed 29.94 kilos, but after using hydrofluoric acid to remove things like the quartz stuck in it, the gold became clearly visible.
The cleaning process meant that the now shiny nugget was left weighing 16.4 kilos (527 troy ounces).
The Crown Jewel was purchased by Ironstone Vineyards located in Murphy, California where it is still on displayed for the public.