VINTAGE Gulf Oil Employee Award Pin. 10 years. 10k Gold w/ Diamond

This tie-tack award would have been given to Uncle George to commemorate 10 years with Gulf Oil company back in the 1930's. My research reveals that it is 10k gold (perhaps gold filled?) and the diamond is genuine. It's tiny- about 1/2" in diameter, and is still in its original box. Subsequent pins were given at each 10 year mark, with a diamond added for each 10 years of service. He was one of the pioneers of the petroleum industry in Texas, and worked as a driller during the early days of expansion after Spindletop. He and Aunt Nen travelled all over the world, arriving after the geologists, to figure out how to get the newly discovered oil out of the ground. Aunt Nen always made it sound like a glamorous life, but sometime boring for her. No doubt it wasn't quite so mundane for Uncle George!