The guitar that almost never was. The Moderne was designed in the 1957, at the same time as the Flying V and Explorer. In 1958 a few prototypes were built, but the guitar design was determined to insufficiently popular to turn into a production model.
As it never progressed from the prototype stage, the 50's Modernes are probably the rarest of all Gibson solid-bodies, if any exist at all. None have been seen since the 1950s, and it is surmised that all prototypes were probably disposed of at the factory. No hard facts exist as to many were built, but estimates vary between about 20-35 units, with as few as 6 being actually completed.
Both the Flying V and Explorer were re-released over the coming decades (in 1967 and 1976 respectively) and in 1982, the Moderne finally got its shot at production.