Spondylus
Not a stone at all, but a shell so vivid the Andes built an economy around it.
A Quick Note: It's Not a Gemstone
Unlike the other stones in this guide, Spondylus isn't a mineral at all; it's the shell of a spiny oyster. We include it here because we treat it the same way we treat our gemstones: hand-selected for color and character, and set the same way in our pieces. If you're looking for a technical gemstone, this isn't one. If you're looking for something with equally striking color and a lot more history, keep reading.
Where It's From
Spondylus comes from the warm coastal waters of the eastern Pacific, primarily off the coasts of Ecuador and northern Peru. The shell we use is sourced through our partners in Lima, continuing a material tradition that runs deep in the region.
What It Is
Spondylus is the shell of a genus of bivalve mollusks commonly called thorny oysters or spiny oysters, named for the spiky projections on their exterior. The interior of the shell is what we use in jewelry: a dense, glossy layer that naturally occurs in vivid oranges, reds, and purples, sometimes all in the same shell. No dye or treatment is involved; the color is entirely natural to the animal.
Cultural History
Long before it was jewelry, Spondylus (called "mullu" in Quechua) was one of the most valuable materials in the ancient Andes. For thousands of years, coastal cultures in Ecuador dove for it and traded it inland to civilizations including the Moche, Chimú, and eventually the Inca, who considered it more valuable than gold. It was offered to mountain gods and water deities in rituals meant to ensure rain and agricultural fertility, buried with the dead, and used as a form of currency across a trade network that stretched thousands of miles along the Pacific coast. Some of the earliest Spondylus trade routes date back over 5,000 years, making it one of the oldest continuously used ornamental materials in the Americas.
Caring for Spondylus
Spondylus is shell, not stone, so it's on the softer and more porous side (roughly 3–3.5 on the Mohs hardness scale). Treat it a bit more gently than a harder gem:
- Avoid water exposure — showering, swimming, and handwashing can dull the surface or cause discoloration over time.
- Keep it away from perfumes, lotions, and household chemicals.
- Store it separately from harder stones or metals that could scratch it.
- Clean gently with a soft, dry cloth. Skip ultrasonic cleaners entirely.