Hello
Some pictures exist, i search .
From memory i can say that
1) French ww1 Explosive shells are Yellow painted (+ black numbers and /or white weight crosses) for 100% trinitrophenol loading (melinite , pikrine, lyddite)
2) yellow (top) and red (bottom) for brassed/mixtures of trinito explosives + nitrates (schneiderite, amatol ...)
3) green for chlorate or perchlorate explosives.
4) 75mm dec Schrapnell shells are red or white (two sorts of mechanism)
5) green with special orange or white markings for gas shells (for example : VIS, white bands, orange bands, N 4 , N 5 ...)
etc ...
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