Actually, these markings often indicate the carat weight of the gemstone in your ring. That is, if the inner band of your ring is marked as 0.50, it indicates that the carat weight of the gemstone in your ring is 0.5 carat.
These markings are one of the best ways to figure out genuine diamond rings. For this, just match such diamond ring numbers on your rings with the carat weight given in your diamond ring appraisal certificate. Plus, these numbers will help the jeweler to identify the exact diamond ring that he is looking for. Moreover, they can easily figure out if someone switches the real diamond ring with its replica.
Analyzing the carat weight of your solitaire ring in this way is pretty easy, but things may get a bit confusing when it comes to a ring that features more than 1 diamond. Here, you will need the help of a gemologist or an appraiser in order to find the Total Carat Weight of the ring or the carat weight of the center diamond alone.