Vintage Sterling Silver with shops Semi-Precious Stones Bib Choker Necklace

This stunning 950 Mexican sterling silver bib collar necklace measures 18", has several favorite semi-precious stones, including Turquoise, Malachite, Lapis Lazuli, Onyx and Tiger Eye. I have not been able to identify the specific maker from the markings except that it says Casa Grande along shops with several other markings. It is very heavy at 79.3 DWT = 120 gr. and extremely well made. With all the different colors this necklace will match any outfit. It's in wonderful condition with a very secure clasp. A real collectors piece.