Sterling Silver USA 831 opal ring

terling Silver USA 831 opal ring. Size 7-8. It is real opal and sterling silver was handmade by the native Americans here in New Mexico USA. It has the signature of the person who hand made. It ( it's hard to see and it is just there brand name they go by not necessarily there name ) I bought it brand new for 75.00 so I'm asking 40.00 or best offer