Help to identify this antique casing

No matter how hard I looked, I cant find what this is. The only information I have is I metal detected several on these in Colorado point in Aruba. That in it self makes me to believe it is of European origin. The caliber is definitely not 45. It looks more like 32. Large rim points to ether early rifle or revolver. Maynard shaped rim is very confusing.
Need help.

Looka like an artillery primer, maybe a Model 1906

WW2 era artillery percussion primer. The headstamp has been partially obscured by someone pounding on it. The USN equivilant would have been a Mk 2.

Delete this double post.

Thank you kindly for your response. You guys made my day. Colorado point in Aruba has 3 artillery bases in the ground from 155 mm US 1918/17 M1 types howitzers which fired on U-Boats attacking refinery a mile away. That refinery was supplying 40% of UK oil reservers during WWII.