Zinc Cased Signal Cartridge Queries

I ask questions about two zinc cased signal cartridges.

  1. All zinc with no headstamp. 82.5mm Length. Knurled rim = red signal.
    The 6mm primer looks hit rather than fired. Some case mouth cracks.
    Two flash holes plus dome when looking inside case. Looks German c.1918?

  2. This is a heavy case with 10mm steel base and 1.4mm thick zinc? case.
    The case is 91.5mm long which is unusual.6 petals = yellow star.
    Looks like the SB paper cases but is it German or experimental? Year?

All information is appreciated as I think they are unusual. Ron.