On the 24th of January 2011, the Espana Post issued the series of stamps devoted to musical instruments features four string instruments, three of them plucked: guitar, lute and mandolin, and the other one, the violin.
The mandolin is a musical instrument with four double strings and a soundboard which can be concave or flat. It is of Italian origin and has been used by many great classical and modern composers both in traditional music as well as in other music styles. Among its variations is the Italian mandolin, folk and bluegrass.
Early mandolins had six double courses of gut strings, tuned similarly to lutes, and plucked with the fingertips. Modern mandolins—which originated in Naples, Italy in the late 18th century—commonly have four double courses (four pairs) of metal strings, which are plucked with a plectrum.Many variants of the mandolin have existed.
A mandolin may have f-holes, or a single round or oval sound hole. A round or oval sound hole may be bordered with decorative rosettes or purfling, but usually doesn't feature an intricately carved grille like a Baroque era mandolin.