This hadith seems to contradict the one where it is mentioned that an Abyssinian stone was inlaid.
Those who are of the opinion that Sayyidina Rasulullah sallallahu alayhe wasallam had two rings, say that this hadith in context is similar to it being two rings. Bayhaqi and others also hold the same view, and according to him there no is complication.
Those who are of the opinion that Sayyidina Rasulluahsallallahu alayhe wasallam had one ring, give the explanation, that by Habshi (Abyssinian) it is meant Habshi colour or Habshi style, or the maker of it was a Habshi.
According to this humble servant the explanation is that there was more than one ring seems correct, because from the hadith it has been proved that at different times Sayyidina Rasulullah sallallahu alayhe wasallam had different rings. Sayyidina Rasulluahsallallahu alayhe wasallam had a ring made for himself. His servant gave him one as a present as is evident from different narrations stated in the book of ‘Jam’ul Wasaa-il’.