Good Morning Chris I did a quick search and did find a brand name "Monte Carlo" - under Cameras, Stopwatches, Binoculars, by J L Galef & Son Inc.
There's probably a number of identical brand names in the English speaking world and also the possibility that JL Galef added a range of pearls under the brand name "Monte Carlo" at a later date and this information hasn't been collaborated. Not sure. If any of our visitors have any information on J L Galef and Sons or "Monte Carlo" please leave your comments.
Your pearls are graduating pearls Chris as they graduate to larger size pearls at the center front. The pearls should be restrung every few years. I have an excellent team of pearl re-threaders here in Australia and also professional jewelry experts who can examine and appraise your pearls and provide a written appraisal of such a high standard that one we be proud to frame!
Great to see the pearls are still in their original box. Please contact if you would like an Appraisal and tick the pearl Appraisal box.
