Ear ornaments such as these often were worn in clusters by Omani women attached to the headdress. They are known as halaq or shaghab.
Hollow, but still heavy in the hand, they are of circular form. Each has spiky section probably in emulation of the thorns that many desert plants in Oman have. They terminate with an elongated sphere and a cluster of balls typically believed to be based on the mulberry fruit.
The two examples here have minor dents associated with age and use.
References
Hawley, R., Omani Silver, Longman, 1978.
Rajab, J.S., Silver Jewellery of Oman, Tareq Rajab Museum, 1998.