I've now found my notes on the Britannia 'De Luxe
' range (not sure of spelling but that's what was written down):
De Luxe range from 1950 used colour (Moss Green, Blue, Amethyst and Ivory inserts
As to what the "inserts" are, I imagine this could either mean the 'cut' decoration or a separate panel of colour like the Waverley example: something at the back of my mind says the latter because I'm sure I've seen an example at some time. If it does have a separate panel it should look very impressive, I reckon.