Hello, this item is a large flat stone relief sculpture depicting motifs inspired by ancient Mesoamerican civilizations, likely Aztec or Mayan. The central mask represents a solar or deity figure, surrounded by warriors or priests holding ritual staffs, carved in low relief with geometric border designs. The material appears to be green serpentine or a similar hardstone, and the carving style reflects 20th-century revivalist craftsmanship rather than an ancient original. The overall symmetry, use of repetitive patterns, and incorporation of mosaic-like inlays suggest it was produced by a skilled artisan referencing pre-Columbian iconography, possibly in Mexico during the mid to late 20th century, when such works became popular among collectors and museums.

In terms of value, mid-century Mesoamerican-style serpentine or stone carvings of this size (39 x 24 inches, 57 lbs) generally sell between 800 and 1,200 USD at auction, depending on the stone quality and execution detail. Authentic pre-Columbian examples would be significantly more valuable, but based on stylistic and technical features visible here, this piece likely belongs to the 1950–1980 period of revival art.