Gatsby Jewellery Ltd has dated this piece to the 1910s.
The diamond set part of the piece is backed in 18k yellow gold and set on a 9k yellow gold pin.

Presented in an antique box.
Cut – Round old cut diamonds in the “feathers” and square step-cut diamonds in the “shaft.”
Colour – H to I.
Clarity – SI1 to SI2.
Carat – Approximately 0.50 carat total.
Measurements – From one end of the pin to the other is 7.1cm. The diamond set segment of the pin is 17.2 x 9mm.
Metal – The diamond are set in platinum backed in 18k yellow gold. The pin is 9k yellow gold.
Gatsby Jewellery Ltd has dated this piece to the 1910s.
Gatsby jewellery are a husband and wife team who have years of knowledge and experience in dealing in fine antique jewellery.
You can view the stock and full dealer information on the Gatsby Jewellery Ltd Profile Page