Could my "silver" ring really be plastic?

I recently purchased a ring that the seller claimed was rhodium-plated silver and is stamped .925 on the inside of the ring. However, after two months of wear, the rhodium is rubbing off between the fingers and what's underneath is rough, dull, and opaque white and appears to be plastic. Is it possible to plate plastic with rhodium and is this a common practice people use to make fake jewelry?

First of two simultaneous responses -- +++++++

You should be able to tell by the weight of the ring. Being the ring is stamped .925 it is supposed to be sterling silver. Since the rhodium has worn off, the silver is subjected to tarnishing and wear. Try a silver polish to restore the lustre. If you work with your hands, avoid wearing the ring - silver is too soft for working person's hands. If polishing won't do the trick, take the ring back for a refund. Silver is not that expensive, so I doubt very much that the seller would even take the chance in marketing fake silver, especially if it has a marking. Good Luck!

Second of two simultaneous responses -- +++++++

Hi Monique Collins
if the ring is really plastic you would have felt the weight so low, I doubt that it is plastic it can be an alloy for sure,my answer is based on the detail on the q.
M Nuwais