A vibrant pair or cobalt enamel hoop earrings c. 1940 in 19.2k gold, which is a Portuguese standard.  There is a possibility that these earrings are much older and were assayed at a later date, as they are very Victorian in style and construction.  

Measure 1 1/8" diameter (3cm).  Weigh 6.9 grams total.  Fully hallmarked with unknown maker's mark. T-bar hinge in good working condition.  Minor ding to one side area, does not affect stability or look.  Enamel intact!