Right, I'm more than a little confused now.
1664 - 1685 Old Gold.
From 1685 I'm assuming they adopted the infantry red of other foot regiments from pictures etc.
1804 RMA was raised, but did not become a separate entity until 1859. It appears that it was 1855 when the tunic colours changed - RMA wore the blue tunics of the other artillery regiments, whilst the RMLI took infantry red again. Prior to this split the RMLI were unusual in being the only regiment of foot to NOT wear red during the Victorian era (both RMA and RMLI wore dark blue tunics). I haven't found a distinct answer as to when they switched from the early red to the blue, but would hazard a guess at 1755 when the Marines were reformed after disbanding for the last time (I believe mess dress was still red at this time).
Wholley, I'm certain the green is Light Infantry green - prior to 1914, all light infantry units were denoted by their dark green cloth helmets (although I can't find anything confirming this to be applicable to RMLI). But the drummer red is a mystery - I remembered RMA being red tunics, but apparently not!! It now seems to make more sense for the red to in fact refer back to the infantry red worn by all Marines prior to RMA/RMLI - I'm still sticking with Sisyphus on being taught red = RMA, even if it doesn't seem to make sense at the moment! I've had a look through that Jack Clegg site - very interesting it has to be said, but focussing on WW1 so not much help here (unless I've missed something).
So that was from a look around the web - far easier to look at official websites! From the RM Band webby, blue is Navy link and the colour of the facings for over 100 years (no dates given, but I'd guess at the run-up to RMLI taking red - incidentally, 'Drummer red' was worn by all infantry units (hence also 'infantry red') up until 1876 when it became scarlet). LI green from the shakos (caps) and bugle strings of RMLI. Old gold we know. So it does look like red being linked to the RMA is a red herring
Someone better tell the DLs
