Diamonds is an album.
=== Compilation album ===A compilation album is a collection of material from various recording projects or various artists, assembled with a theme such as the "greatest hits" from one artist, B-sides and rarities by one artist, or selections from a record label, a musical genre, a certain time period, or a regional music scene
 The term is particularly associated with popular music where separate tracks are known as album tracks; the term is also used for other formats such as EPs and singles

