an ambo once showed me how to get a ring off hope i can explain it properly
get a length of string & put it about an inch out under the ring facing the back or palm of you hand then with the other long end wind it tightly around your finger (can be a bit painful) tillpast the knuckle then get the short end & slowly pull it - ring should unravel off your finger - i also used some liquid soap but it has worked a few times with me & avoids the ring being cut