Commemorative coin in the context of "Coinage of the United States"

Silver coins are one of the oldest mass-produced form of coinage. Silver has been used as a coinage metal since the times of the Greeks; their silver drachmas were popular trade coins. The ancient Persians used silver coins between 612–330 BC. Before 1797, British pennies were made of silver.

As with all collectible coins, many factors determine the value of a silver coin, such as its rarity, demand, condition and the number originally minted. Ancient silver coins coveted by collectors include the Denarius and Miliarense, while more recent collectible silver coins include the Morgan Dollar and the Spanish Milled Dollar.

A gold coin is a coin that is made mostly or entirely of gold. Most gold coins minted since 1800 are 900–920 ‰ gold (22‑karat), while most of today's gold bullion coins are pure gold, such as the Britannia, Canadian Maple Leaf, and American Buffalo. Alloyed gold coins, like the American Gold Eagle and South African Krugerrand, are typically 917 ‰ gold by weight, with the remainder being silver and copper.

Until about the 1930s, gold coins were circulation coins, including coin-like bracteates and dinars. Since then, gold coins have mainly been produced as bullion coins for investors and as commemorative coins for collectors. While modern gold coins are still legal tender, they are not used in everyday financial transactions, as the metal value invariably exceeds the nominal value. For example, the quarter-ounce American Gold Eagle has a denomination of $10, but a metal value of approximately $500 (as of January 2024).

€2 commemorative coins are special euro coins that have been minted and issued by member states of the eurozone since 2004 as legal tender in all eurozone member states.

€2 coins are the only denomination intended for circulation that may be issued as commemorative coins. Only the national obverse sides of the commemorative coins differ; the common reverse sides do not. The coins typically commemorate the anniversaries of historical events or current events of special importance.

The Denver Mint is a branch of the United States Mint that struck its first coins on February 1, 1906. The mint is still operating and producing coins for circulation, as well as mint sets and commemorative coins. Coins produced at the Denver Mint bear a D mint mark (as did the Dahlonega Mint, which closed before the Denver branch opened). The Denver Mint is the single largest producer of coins in the world.

Platinum coins are a form of currency. Platinum has an international currency symbol under ISO 4217 of XPT. The issues of legitimate platinum coins were initiated by Spain in Spanish-colonized America in the 18th century and continued by the Russian Empire in the 19th century. As a form of currency, these coins proved to be impractical: platinum resembles many less expensive metals, and, unlike the more malleable and ductile silver and gold, it is very difficult to work. Several commemorative coin sets have been issued starting from 1978 and became popular among coin collectors. The major platinum bullion coins include the American Platinum Eagle, the Canadian Platinum Maple Leaf, the Australian Platinum Koala, the Manx Noble, the Chinese Platinum Panda, the Austrian Vienna Philharmonic and several series by the Soviet Union and later by the Russian Federation.

The Arch of Claudius was a triumphal arch in Rome built in honour of the emperor Claudius's successful invasion of Britain in AD 43. It was dedicated in AD 51 but had already been anticipated in commemorative coins minted in AD 46–47 and 49, which depicted it summounted by an equestrian statue between two trophies. However, the real structure was a conversion of one of the arches of the Aqua Virgo aqueduct at the point where it crossed the Via Flaminia, the main road to the north, just north of the Saepta.