Columbia label designs
Below are all known UK label designs for Columbia catalogue sequences that included classical repertoire between the end of WW2 and the end of 1959. All sequences are mono, unless stated. All sequences concentrated singly on classical music, unless stated (at least, I'm not yet sure about the DX/DB series yet).
The pre-war LX example shown below was still on catalogue in the 1950s.
The Green label design was also used on popular music sequences. With stereo labels, the second letter of the prefix matches those of the Blue and Green mono sequences. All other stereo sequences with classical repertoire (SBO and SCX) have the same label design, though some backgrounds look whiter and some look greener.
7" SPs (Short Play)
The SP format, now better known as 'singles', was confusingly originally viewed as a Long Play format (i.e. stacked on an autochanger record player, as per earlier 78 'albums'). The first releases, all from EMI, had a large centre hole as per the original US RCA Victor format, for playing on early 45 rpm players with large spindles.
The SEG Green Label sequence was a popular music sequence, though there were no completely classical releases during the period covered, hence its exclusion below. Yes, there are lots of releases by Felix Mendelssohn, except that this is the other Felix Mendelssohn - i.e. Felix Mendelssohn and His Hawaiian Serenaders.