American, out of Chicago.  Mercury was started in 1945 by Irving Green, Berle Adams and Arthur Talmadge.  In Britain its records were licensed to Bruswick initially, and to Oriole from 1952; Oriole introduced an actual Mercury label in 1954 (12).  Mercury moved to Nixa / Pye in 1956, and scored a string of successes from 1956-60 with Vocal group The Platters.  The labels kept the 'flowing script' logo, but turned from black to blue (1).  EMI took over manufacture and distribution in late 1958, at which point the logo shrank and was enclosed in a pair of ellipses (2).  During both the Pye and EMI periods EPs had basically the same labels as the singles did, although in the EMI years there was a red-labelled Olympian series, which was dedicated to Classical music (13), and a blue-labelled 'Emarcy' series for Jazz (14).  When Mercury was bought by Philips in late 1963 the colour and logo remained unchanged, but the Philips 'grid' appeared and there were changes in the various legends and typefaces (3).  In December 1968 the logo was simplified slightly: the 'Records' was dropped, along with one of the ellipses (4).  As a member of the Philips family Mercury became part of Phonogram in the early '70s, along with its parent.  The '70s and '80s brought more Chart hits, with the likes of Rod Stewart, the Bachman Turner Overdrive, 10 c.c., the Steve Miller Band, and Rush registering in the Rock field, while artists such as James & Bobby Purify, the Ohio Players and Don Covay scored in the Soul / Disco area.  Mercury continues to release records today (2006) as part of the Universal Music group.
Singles in the early '70s had paper labels, which were often 'dinked' at the factory and provided with triangular 'spiders' (4).  From 1973 injection-moulded labels were used, in a variety of colours.  Silver appears to have been the first colour used (5) but it was soon replaced by fawn (6).  Metallic silver-blue came into use in 1978, and replaced the fawn in 1979 (7).  Very occasionally singles came in other colours, such as purple, red (8) white (9) and lime green (10).  Sometimes the same single can be found in more than one colour (7, 8), or with both paper and injection-moulded labels (4, 9).  The paper label from 1978 (11) seems to be a Pye contract pressing, while the EP with the white paper label (19) was a product of Phonodisc's Special Products division and was made for Yardley's - the scan appears by courtesy of Robert Bowes.  Late 1950s sleeves were red-and-cream (20).  The tartan (21) variety dates from the early '60s; mid '60s ones were pink and white (22), which evolved into red-and-white (23).  Initially the red-and-white sleeves were printed sideways-on - the opening on the one shown is at the right-hand side.  Early '70s company sleeves (23) were soon replaced by standard Phonogram Group ones (25, 26).  The white demo (15) dates from the 1950s and EMI; later EMI demos had a solid red 'A' across them (16).  Early Philips demos had 'Sample Record' on them either in the form of a sticker or a crude yellow hand-stamp; later ones had the usual family 'Hollow red A on white label' design (17). 
Oriole Mercurys seem to have had the same numbers as their American counterparts; after the move to Pye a 7MT-100 series was used for singles, EPs being numbered in the MEP-9000s.  These numbers changed to the AMT-1000s for singles and ZEP-10000s for Popular EPs at the time of the switch to EMI; Stereo EPs had their own SEZ-19000 series, while Classical ones were numbered in the XEP-900s and Jazz ones in the YEP-9500s. The Pop numbers changed to the MF-800s for singles and the 10000-MCEs when Philips took Mercury over.  From 1970, when Phonodisc scrapped lettered prefixes and replaced them with numbered ones, Mercury singles were given a 6052-000 series; this lasted until 1974, after which time several different series were used alongside one another, notably 6167-000, 6008-000 and 6007-000.  Presumably the different prefixes indicated the place of origin of the record - certainly 6167s appear to be American, while 6007s and 6008s are mainly British.   Some releases were considered important enough to be given their own catalogue numbers, with appropriate prefixes - for example, DUSTY-1 was a Dusty Springfield single.   The discography below, which has many gaps, only covers the 1970s; most of the gaps are due to the fact that those numbers were not used for British releases.  I have grouped the various blocks of numbers together, rather than attempting to put the releases into chronological order.

Copyright 2006 Robert Lyons.