Vtg Navajo JG Sterling Red Spiny Oyster Pendant w 925 Silver Chain 15.5”

Vtg Navajo JG Sterling Red Spiny Oyster Pendant w 925 Silver Chain 15.5” Vintage Navajo sterling silver pendant made by JG Sterling, Red spiny oyster stone - small flaw in photographs - I am unsure if this is naturally occurring or not but it is very small, please see close up photos. Red spiny oyster with cream/white & hints of yellow. Pendant measures approx 1.9” chain measures 15.5”