Sonoran turquoise is mined in the state of Sonora in northern Mexico, in the same great copper belt that runs up through southern Arizona. Geologically it is close kin to the Arizona mines; politically it is a different country, and we label it accurately rather than folding it in with Arizona turquoise, because provenance is the thing serious turquoise buyers actually care about.
The material has a reputation for being unusually hard and bright. Two looks dominate what reaches the market: a vivid blue-to-green stone shot with golden or bronze pyrite, often sold as Sonoran Gold, and a clearer light blue with fine smoky matrix. Both take a high natural polish, which is part of why cutters like it.
The practical advantage of Sonoran is that Mexican mines are still working. Where a stone like Sleeping Beauty is finite — that mine stopped producing turquoise in 2012 — Sonoran material continues to come out of the ground in small but real quantities. If you want strong colour without paying the scarcity premium that the closed Arizona mines now carry, this is a sensible place to look.
How to judge it: look for saturated colour rather than pale washed-out blue, a hard glassy polish without pitting, and matrix that reads as a deliberate pattern rather than as dirt. On the golden-matrix material, the pyrite should glitter cleanly against the blue.
This is a smaller collection — around 78 pieces, handmade with natural stones in sterling silver — and many are one of a kind, so it turns over. Browse the full turquoise collection or read the Turquoise Guide. Silver Star Jewelry, 7257 East First Ave, Old Town Scottsdale, (480) 949-1101, open every day. Free shipping within the US over $99.