This crescent is a bit different, with a split curve to it, the main part set with alternating old cut diamonds and rubies, and the outer part with a scalloped edge, set with split pearls. 
This was originally a late Victorian brooch, which we have lovingly converted into a pendant, adding a 6mm jump ring of recycled gold. 
Tests as 9ct gold 
Weight approx 4.72g 
Total drop approx 34mm
Width approx 26mm
Very good antique condition