Online dating is unsafe unless you are an adult (18 years or older). If you are a minor, you should tell your friend that it's a bad idea, however if you are an adult you should be able to handle yourself and probably shouldn't be asking things like this on Brainly or similar websites because it could be seen as targeting children.
The brooch value would be increased by its provenance. It’s very likely that its market value would be a lot just because it’s an artifact which was once owned by the historical figure.