It is a stone recomposed with Turquoise, spondylus (thorny oyster) and Bronze., pressurized into plates, then cut into cabochons. The spiny oyster shell comes primarily from the Sea of ​​Cortez off the east coast of Baja California and Mexico. Its color can range from light yellow to dark red and some shells are purple.

The Incas called the spiny oyster mullu and used the shell as an offering for rain and good harvests in the spring.
The shells of the spiny oyster go well with turquoise and have been used as an ornament since ancient times by American Indians.