Oscar Heyman Brothers diamond horse brooch. A yellow gold brooch in the form of a horse's head with reins and bridle. The reins are set with 50 round brilliant cutdiamonds, F colour, VS1 clarity with an approximate combined weight of 0.59 carats in open backgrain settings, further adorned with a single round brilliant cut diamond in a closed backrubover setting, with a weight of 0.01 carats. The total approximate diamond weight is 0.60 carats, to a lifelike horse head brooch featuring a mottled gold texture, polished bridle detail and a sweeping rein design, the reverse mounted with a secure hinged pin and safety catch, approximately 3.50 cm in height. Marked 18 carat yellow gold and platinum, makers mark for Oscar Heyman Brothers, numbered '200776', circa 1970.