Gatsby Jewellery Ltd has dated this piece to the 1910s.
The cluster hangs from a lever backed setting crafted in yellow gold with an old mine cut diamond set in a hexagonal platinum settings. Curiously, the bottom part of the lever backs are in 15k rose gold, although they don't appear to be replacement fittings.

Cut – Rose cut diamonds in the cluster, with an old mine cut diamond set above.
Colour – G toH.
Clarity – SI2 to I1.
Carat – Each cluster holds approximately 0.21 carat, with each of the old cuts diamonds weighing approximately 0.05 carat.

Circa – 1910.
Condition – One of the rose cut diamonds in one of the cluster is chipped at the edge. This isn't visible to the naked eye.
Measurements – From the top of the top diamond to the bottom of the cluster is 15.6mm. Each cluster is 6.85mm in diameter.
Metal – All the white metal is platinum. The rose and the yellow gold are 15k. Tested.
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.
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