This little-known Christmas single by T.Rex may not be a classic, but it’s not bad enough to merit being left on the shelf until long after Marc Bolan’s death.

Christmas Bop, featuring his girlfriend Gloria Jones on backing vocals, was initially set for release in December 1975 and EMI had printed up labels, but not the actual vinyl; two of those labels sold 20 years ago for £896.

The plan was to put Telegram Sam and Metal Guru – arguably the best two T.Rex singles – on the B-side but the singles were never pressed and the song never saw the light of day until 1982, two years after Marc’s death.

Even then it was only distributed as a Christmas gift for fan club members, and there’s another more synthy-sounding version of the three-track single that appeared on a 1994 compilation of unreleased singles – Messing With The Mystic – and in 1996 as Marc’s Christmas Box, and on the 1997 compilation The Best Of The Unchained Series.

So it’s not exactly obscure, even if I hadn’t herard it til now. And it came out again on Bandcamp as the dreadfully named T-Rexmas EP in 2011, the same year a small snippet of the song appeared briefly in an American TV ad.

It’s got what you could call classically Bolanesque lyrics, with Marc encouraging us to “get on your silk jeans and your space shoes”, and blends its choppy guitar chords with a hint of Jones’s fondness for soul and disco, along with a lavish Spectoresque production.