Which three metals are not suitable for coinage, and why?

Well coinage metals are exactly what they sound like, they're precious metals used to make coins, so obviously they're not very reactive or corrosive, otherwise ... they're able to portray different oxidation states depending on the complex they're a part of, and they make good conductors (copper and gold used for wiring). read more

Historically, most coinage metals (or alloys) are from the three nonradioactive members of group 11 of the periodic table: copper, silver and gold, the copper usually being augmented with tin and often other metals to form bronze. Gold, silver and bronze or copper were the coinage metals of the ancient world, and most medieval coins. read more

Two important properties of coinage metals are hard and unreactive.Some examples of metals that are used in coinage are copper, silverand gold. read more