What is Fool’s Gold?
While it’s exciting (and often profitable) to pan for gold or use a metal detector, how can you be sure that what you’re finding is the real thing? If it looks like gold, what else could it be? It could be fool’s gold which is actually pyrite.
While gold is a precious metal, pyrite (also known as iron pyrite), isn’t even a metal. It’s an iron sulfide mineral that has a metallic luster. It is very common and found throughout the world, even sometimes along seams of real gold. Sometimes it has a gold color very similar to gold, although not always.
Pyrite is most often found with veins of quartz, another mineral, in sedimentary and metamorphic rock, and, commonly, in seams of coal or with other fossils. Like quartz, pyrite grows with a pronounced crystal structure, which makes these minerals appear as conglomerations of cubes.
Another variation of fool’s gold is a reflective mineral called marcasite is what’s known as a polymorph of pyrite.
This means that it has a similar mineral constitution, but has a different crystallic pattern. As with pyrite, sometimes it has similar gold coloring to gold, and sometimes it doesn’t.
So how can you tell the difference between real gold and fool’s gold? If it’s large enough, you can usually see the crystal structure of fool’s gold which real gold does not have. Gold generally has a smoother appearance, with no angles.
Fool’s gold is much more brittle than gold, and will crack, break, or even pulverize when struck against a rock. Pyrite and marcasite actually have a sulfurous scent when pulverized. Because of pyrite’s high iron content, it can give off sparks when struck with a metal object.
Another way to be sure you have real gold instead of fool’s gold is to test it. Read my post on How to Test Gold at Home or When Traveling to find out how.
The bottom line? When in doubt, hang onto it! Test your nugget. If it’s not gold but it’s pretty, hang onto it anyway! It might not have much financial value, but can be a decorative souvenir that you will treasure, reminding you of one of your treasure-hunting adventures.