Vintage sterling Taxco Aztec double sided heavy pendant necklace

Stunning silver, copper, and brass? with crushed mosaic turquoise large pendant necklace with chain. Double sided with person and aquatic animal on one side and symbol on opposite side. I have not found any markings, but this is believed to be a Taxco Mexico piece from around 1940. 2” diameter pendant without bale. 24” rope necklace. Unisex.