antique broach/pin

What a lovely piece to have in your family. It's a miniature of the goddess Victoria, also known as Nike (yes like the shoe company) or Winged Victory. Images of Victoria were particularly popular in association with Queen Victoria of England, and I'd definitely date this piece from her reign (1837-1901), probably the last quarter and quite possibly from 1897 when the entire British Empire --the largest empire in the world at that point-- celebrated her sixtieth year on the throne with the Diamond Jubilee and a lot of Victoria-related memorabilia.

I would say it was made either in England or France (for export) and would've been a gift a comfortable middle class British woman would've been happy to recieve.

There are good arguments to be on either side of whether the stones are diamonds. It was certainly not unusual for pendants and brooches of the time to be ornamented with small mine-cut diamonds and the enamel and painting some places is quite fine enough believe the artist would work in small gemstones. However, one would usually expect a hallmarks (maker's signs) and a more detailed overall finishing in fine jewelry.

This a lovely brooch and you should be pleased to have it in your family. It's difficult to put a price on a piece I haven't seen in person, and of course its true value as an heirloom is priceless. Assuming the stones are not diamonds, I would put the market value on this between $150 - $300 USD.