Fool’s Gold

Happy April Fool’s Day! To celebrate, we thought we would discuss the most common trick that is visited on the unseasoned prospector: Fool’s Gold.

Fool’s Gold is a sulfide mineral better known as pyrite or iron pyrite. While it is shiny and pale yellow and often found in veins of quartz, that is the extent of it’s resemblance to gold. Visually, gold has a naturally irregular shape (the technical term is anhedral) while pyrite has a crystalline form. Also, pyrite has a lighter yellow hue compared to the the rich shade of pure gold. Structurally, gold is particularly notable for it’s low melting point and malleability while pyrite is hard and brittle. If you hit a gold nugget with a hammer, it would be smashed flat. If you hit a piece of pyrite with a hammer, it would shatter. This is why a classic test of gold has been to bite it. True gold can be conform the the force of your jaw.

Pyrite does have its uses. When struck, it will produce a spark, which made it notable even back in Roman times and was used as ignition in early fire arms. Today, it is used in many manufacturing industries. Pyrite is a natural semiconductor, used as a cathode in batteries. Moreover, while it isn’t gold, that hasn’t stopped jewelers for using it in jewelry.