And you thought an Olympic gold medal was made of gold

Another great graphic from Compound Interest:

Rio-Olympic-Medal-Compositions

So a gold medal is a silver medal with gold plating? And more surprising, the bronze medal is really brass.

Comparison chart

Brass versus Bronze comparison chart
Brass Bronze
Properties Higher malleability than zinc or copper. Low melting point (900 c); flows when melted. Combinations of iron, aluminum, silicon & manganese make brass corrosion resistant. Susceptible to stress cracking when exposed to ammonia. Not as hard as steel. Hard and brittle. Melts at 950 centigrade but depends on amount of tin present. Bronze resists corrosion (especially seawater corrosion) and metal fatigue more than steel and is also a better conductor of heat and electricity than most steels.
Composition Brass is any alloy of copper and zinc. Bronze is a metal alloy consisting primarily of copper, usually with tin as the main additive, but sometimes with other elements such as phosphorus, manganese, aluminum, or silicon.
Color Muted yellow, somewhat similar to gold, but duller. Reddish brown.
Uses Decorative; Low-friction applications (locks, gears, doorknobs, ammunition, valves); Plumbing/electronics; Musical instruments for acoustic properties; Zippers & uses where it’s important to negate spark(fittings & tools around explosive gas). Used in boat and ship fittings, propellers and submerged bearings because of resistance to salt water corrosion. Widely used for cast bronze sculpture; Bearings, clips, electrical connectors and springs; For top-quality bells and cymbals.
History Brass was first known to exist in about 500 BC. Bronze dates to about 3500 BC.

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