George Harrison, who was the de facto expert in guitars of the Beatles, owned a 6120, among others. Remind that a guitar from another brand, a Rickenbacker which was one of George's favorite instruments, was sold for $ 660K including premium by Julien's on May 17, 2014.
John Lennon, interested in the sound of George's Gretsch, bought in his turn in 1966 a Gretsch 6120, a Chet Atkins Nashville model manufactured in 1963. At that time, the Beatles were seldom on stage and this instrument was not used in concert.
It is however one of the most prestigious guitars of John who used it in the Paperback Writer session of recordings at Abbey Road on April 14, 1966.
Rock and roll may sometimes be a family affair. In the following year, a cousin of John named David Birch would in turn like to create a group. John presented his Gretsch to David who kept up to now.
It is estimated in excess of £ 400K, for sale on November 23 in London by TracksAuction, lot 214. Here is the link to the site of the auction house.
I invite you to play the video shared on YouTube by TracksAuction: