I weighed it and it's about 7.5 oz. compared to a regular steel cylinder of almost 8oz. , so it has some alloy in it. Extractor rod same material. No markings on it at all.
I don't think it's brushed nickel as under the trun line it shines so it's not coated blue steel. It's also not chrome. I got it 10 years ago-
Well if it's a 6-shot 44 are you sure it's not because they were a shorter cylinder to begin with? The original 624 and 625 used shorter cylinders than the regular 44mag and 45LC.
I just measured a 624 cylinder and its 1.580-1.585" long.
Are you sure that isn't for a 45ACP gun? I too think it's
stainless steel. (Or steel in the white that has been kept in a vacuum).
Can you measure the cartridge length inside the cylinder?
If it's for a .44 Russian then it would be interesting!
Give us more data like the throat bore and cartridge
width and length.