I have a paperweight, or what I believe is a paperweight, it is a wood block with a 20mm Oerlikon casing bolted to it, headstamp is NOEN 20 M.M. MK. 4 1945. There is an engraved plaque on the front that reads 100,000,000th Oerlikon Cartridge Case Made By Northern Engraving & Mfg. Co.
I will try to get a picture of it up on here soon.
Any information of any kind would be greatly appreciated. I am unsure if this is something highly collectible and valuable, or just an every day sort of find. Thanks.