Vintage necklace with green faceted glittering stone

I received this necklace with some other jewelry from my mother's estate when she died at 98 years-old. I do not see any markings indicating that it is actually gold. Nonetheless, it is in excellent condition. The attached chain is lovely and there is an extension with a lobster claw clasp. Thus, you can adjust the length of the necklace. I am assuming the green faceted stone is a crystal. The top of the necklace is a gold bow with small white crystals. There are no markings to indicate the jewelry brand.