I don't know a thing about this bottle but I think it's worth cleaning as best as possible leaving the top intact and displaying just because of the VERY odd shape.
Not a perfume, olive oil, most likely - fairly common shape for 1930's era olive oils and similar food bottles, the Conti brand is still in use today. I'd get rid of the rust blob that was the cap if you don't like it; it doesn't add anything to the value.