This appears to be a form of "trench art" . I believe it is a 37mm artillery shell casing from the great war. The chain appears to have come from a cavalry helmet from the same period. I believe it is a small candle lantern. Trench art was done by soldiers to fight boredom and by civilians to make a few extra pennys. My mother had 2 bud vases made and engraved in the same fashion. Nice job on your restoration.
Bardzo świetnie jest to odrestaurowane i odnowione tylko na przyszłość proszę robić przed czyszczeniem elektrolize tych zrogowaciałych przedmiotów pozdrawiam twórcę tego filmiku serdecznie 👍👍👍👍👍👍