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How is pyrite different from gold?

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A diagram showing the periodic table entry for gold, with the symbol Au, atomic number 79, atomic weight 196.96657, electron configuration, and labels for its properties as a solid transition metal with a face-centered cubic crystal structure. — gold The precious metal gold is a chemical element with the symbol Au. Its square on the periodic table details some of its properties, including its atomic weight, atomic number, and crystal structure.

Pyrite is frequently mistaken for gold due to its brassy yellow appearance, which is why it is commonly referred to as "fool's gold". However, the two are fundamentally different substances:123

Chemical Composition: Gold is a chemical element (Au) found in nature in a relatively pure form. In contrast, pyrite is a mineral composed of iron disulfide ( $F e S_{2}$ ), containing approximately 46.67 percent iron and 53.33 percent sulfur by weight.43
Physical Properties: When struck by metal, pyrite emits sparks—a property that led to its name, derived from the Greek word for "fire". Gold is a highly malleable metal known for its durability and density, whereas pyrite is a brittle sulfide mineral.34
Utility: While gold is a precious metal valued for its beauty and rarity, pyrite has historically been used as a source of sulfur for sulfuric acid production and was once used in wheel-lock guns to produce sparks.23