UNICORN 17 jewel incabloc watch

[jaybee016]

Hello all, was just wondering if someone could tell me anything about this watch. It was handed down to me 22 years ago when I was 21. My great grandmother told my mother before she passed it was to be given to me. Ive worn it twice in the last 22 years on special occasions, however the last time I wore it the safetly chain which is very very delicate broke. A specialist jeweller told me he was too afraid to touch it due to it being so old and valuable. It is marked 9ct, all of the maracsite are secure with none missing. My great grandmother was born in 1905 and passed in 1976, Im told this was passed on to her from her family - Ive no idea - so I thought I'd ask if anyone on here would know as Ive read that UNICORN were connected to a Rolex