Fascinating how these threads can meander...
Pettman cement, or one recipe thereof, consists of:
Gum shellac..............7 parts
Methylated spirit.......8 parts
Stockholm Tar..........5 parts
Venetian Red...........21 parts
I've made it using Jeweller's Rouge instead of Venetian Red, but then both are actually high purity Iron (III) oxide... or rust to most people. It has a blood red colour and has a similar consistency to the paints used to denote the grenade filling bands. Making it is the easy bit. I'd be very interested if anyone has a method of "unmaking" 90 year old Pettman cement; it has defeated every solvent that I've tried.
I suspect some WWI Mills grenades were daubed around the top with Pettman cement, rather than red paint, to denote having been filled. Many WWII No.36s, and 36's from the 1960's and 1970's, had the whole outside of the filler screw covered with Pettman cement. The photo of the 1965 No.36 shows such. The surround of the filler is original cement, while the badly scratched face of the screw I covered with new cement - it did have the remains of an original covering but it was in poor shape.
And on the subject of Pitchers (Mike), here's a service No.13 in original paint, albeit the worse for wear.
Tom.