PATTERN, PROTOTYPE, SPECIMEN OR TRIAL COINS

Patterns are trial pieces which may or may not be issued for general use. During the period when new coin proposals are being considered, several trial strikes are authorized for examination before finalizing the process. The rejected pieces not put into production are known as patterns. Patterns may have minor to major differences compared to the final coins. The type or quality of metal used may be different. The design may also vary in small detail or showing entirely new motifs. Most of these rejected patterns are beautiful works of art and have a special appeal to collectors due to its numismatic and historical importance. Most pattern coins are extremely rare and much sought after by collectors.
Patterns may also emerge where the design has been modified or altered somehow prior to the production process. Patterns are usually uniface and may bear words such as "Prototype", "Specimen", or "Trial". "Prova", "Prueba" or "Probe" is indicative of "test" in other languages.
In many cases patterns are similar to the issued coins, but made of different metals and should not be confused with off-metal strikes "(OMS)", i.e. error coinage struck in other than their officially authorized compositions. Collectors of Germanic coinage may be familiar with the term "Abschlag" which readily identifies similar types of coinage.
In conclusion, pattern coins are a fascinating part of the numismatic history demonstrating the changes applied to the coinage over the years.