Q: Can Muslim females wear imitation rings?
A. Imitation jewellery, including rings, bangles, etc. is not allowed because the Messenger of Allah (Sallallaahu Alayhi wa Sallam) prohibited the use of metal jewellery besides gold and silver. This includes all types of metal such as copper, brass, etc, and the reason was that these types of jewellery were used by the idol worshippers. On this basis, it appears that ornaments made from plastic would be allowed since it (plastic) does not fall under this category and it's not a metal. (Raddul Muhtaar V26 P364, Al Jauharatun Nayyirah V6 P154)