Unfortunately, it might not be able to determine the type(s) of coloured stone in a ring in photos in good lighting, and your photos of the ring were taken in the shade.
In addition to better photos, more information will be required, such as the type of metal that was used to make the ring - there is a big difference in price between Silver and Gold, and also between 9K and 18K Gold etc...
Perhaps some history about the ring, such as how did it come to your possession, and how old you believe it could be.
This ring belonged to my mom. She has had it for years, but I no idea when she bought it or where. I have attached more pics. One of the pics is the inside of the ring. The only mark I see on it are the numbers 925. Other than that I dont see anything else.
925 means silver, so my guess is that the stones are costume jewelry (synthetic) or heavily treated. Unfortunately unlikely worth anything, but pretty!!
I was typing pretty much what lovedogs just sai. 925 is sterling silver, which is relatively inexpensive so not typically used for high value stones. I wouldn't expect it to sell for more than a few bucks, secondhand. You could shine up the metal by dropping it into a jar of sterling silver jewelry cleaner, if you wanted to.
I would guess you are looking at kunzite or something synthetic just based on colour, clarity and size. I think looking at it that synthetic is slightly more likely -- but I could be wrong. It's possible someone can tell you more by using a presidium gem tester or something that checks refractive index on it.