10K Gold & Natural Opal Vintage Ring - KSK

This lovely gold and opal ring is stamped 10K KSK. Possibly made by the KSK Jewelry Company of NYC, dating back to the 1940-50's. There is a very tiny chip or blemish at one end of the stone that is difficult to detect. See the last three pictures. It is at the top of the stone. A beautiful ring. Even better in person! It is approximately a size 6 3/4. Questions welcome. From a smoke free home.