world war one - What's this 1917 shell casing, more exactly

I've been gifted this vase that is obviously made out of a large shell casing. It has 'MARZ 1917' stamped on the bottom, plus other less understandable markings: 'St', 'G', '36', 'HL 25'. I'm attac

WW1 German Cartridge Case Markings - Arms and other weapons - The Great War (1914-1918) Forum

3-inch gun M1917 Artillery Round base cover my dad found in the basement of our 1957 rancher. : r/mildlyinteresting

Brass shell casing - 1917 - General Ammunition Discussion - International Ammunition Association Web Forum

Original France WWI French “Souvenir de la Guerre - 1917” Austrian Ber – International Military Antiques

Ww1 shell hi-res stock photography and images - Alamy

Heavenly Metal: How Trench Art Keeps the Memories of Soldiers and Their Service Alive

WW1 1917 Western Front Bailleul 6 Pounder Trench Art Shell Case - Sally Antiques

Brodie helmet - Wikipedia

1917 Shell Casing

World War I French Trench Artillery Brass Shell Casing Vases, Dated 1917 at 1stDibs trench art shell casing, ww1 artillery shell casing, french 75mm artillery shell for sale

Battle of Vimy Ridge The Canadian Encyclopedia

Large calibre markings (The Western Front Museum)