Common Collection Themes

A few common themes are often combined into a goal for a collection:

Some colonial coins of Ceylon.
Country collections: Many enthusiasts focus their collection on only a single country—often their own. In contrast, some collectors attempt to obtain a sample from every country that has issued a coin [16].

Year collections: Rather than being satisfied with a single specimen of a type, a great many collectors collect type by year; for example, one Memorial Lincoln Cent for every year from 1959 (the year it was first minted) to present. This is perhaps one of the most practical ways to collect a national currency since probably the majority of coin reference books and coin albums catalogue in the same manner [17].

Mint mark collections: Many collectors consider different mint marks significant enough to justify representation in their collection. When collecting coins by year, this multiplies the number of specimens needed to complete a collection. Some mint marks are more common than others [18].

Variety collections: Because mints generally issue thousands or millions of any given coin, they use multiple sets of coin dies to produce the same coin . Occasionally these dies have slight differences. This was more common on older coins because the coin dies were hand carved. But differences—intentional or accidental—still exist on coins today. Generally this is in a very small detail, such as the number of leaves on the ear of corn on the recent US Wisconsin state quarter File:2004 WI Proof.png [19].

Type collections: Often a collection consists of an examples of major design variants for a period of time in one country or region. For example, Euro coins carry a "common side" that shows the denomination and a "national side" that varies in design from state to state within the Eurozone. Likewise, a type collection might focus on an unusual design feature such as coins with a hole in the middle, coins that are not circular in shape or coins with brockage[20].

Composition collections: For some, the metallurgical composition of the coin itself is of interest. For example, a collector might collect only bimetallic coins. Precious metals like gold, silver, copper and platinum are of frequent interest to collectors, but enthusiasts also pursue historically significant pieces like the 1943 steel cent or the 1974 aluminum cent [19].

Coins featuring eagles.
Subject collections: Collectors with an interest in a certain subject (such as, ships or eagles) may collect only coins depicting that interest [18].

Period collections: Collectors may restrict themselves to coins of the 18th or 19th century, while others collect ancient and medieval coins. Coins of Roman, Byzantine, Greek origin are amongst the more popular ancient coins collected[21]. Some collect coins minted during a particular ruler's reign or a representative coin from each ruler. Collectors may also take interest in money issued during the administration of a historically significant bureaucrat such as a central bank governor, treasurer or finance secretary. For example, Reserve Bank of India governor James Braid Taylor presided over the country's move from silver currency to fiat money[22]. Coins reflect the events of the time in which they are produced, so coins issued during historically important periods are especially interesting to collectors [19].

Printed value collections: A currency collection might be modeled around the theme of a specific printed value, for example, the number 1. This collection might include specimens of the US 1 dollar coin, the Canadian Loonie, the Euro, 1 Indian Rupee and 1 Singapore dollar.

Volume collections (Hoards): Collectors may have an interest in acquiring large volumes of a particular coins (e.g., as many pennies as they can store). These usually are not high-value coins, but the interest is in collecting a large volume of them either for the sake of the challenge, as a store of value, or in the hope that the intrinsic metal value will increase[10].

A false 20 Lira coin, 1927. With the head of Benito Mussolini on the obverse, this is an obvious copy. Italian coins during the fascist period bore the portrait of King Victor Emmanuel III[23][24].

Copy collections: Some collectors enjoy acquiring copies of coins, sometimes to complement the authentic coins in their collections. Copies might be:[25][26][27][28]
contemporaneous ancient copies minted as official coins by other cities or rulers
contemporaneous ancient copies minted as counterfeits (often gold- or silver-plated) to fool merchants and consumers
contemporaneous modern copies minted as counterfeits to fool merchants and consumers
modern copies of older coins minted as forgeries to fool collectors
modern copies sold as replicas (often, but not always, marked as such)
modern copies minted for museums to be displayed instead of the originals
modern copies made to be used in jewelry
modern copies as official circulating coins that pay tribute to the original coin
modern copies as bullion collectible coins that pay tribute to the original coin
modern copies as medals or tokens that pay tribute to the original coin

Collecting counterfeits and forgeries is a controversial area because of the possibility that counterfeits might someday reenter the coin market as authentic coins, but US statutory and case law do not explicitly prohibit possession of counterfeit coins[21].