The traditional tooling, soldering and cutting techniques were among the first learned from the Spanish New Mexican smiths and harness workers the US Army hired to maintain their equipment needs. A story tells of how the usually observant Navajo might have learned metal work to duplicate the puched metal rations cards issued by the Army. In any case, they learned the craft and adapted it to their cultural designs as well as adopting many early colonial Spanish ones such as the concha, and the "naja", a horseshoe-like form found at the bottom of necklaces and on bridles. This "good luck charm" dates back to 15th Century Spain, and may be an early Moorish influence. Much later, stone setting and cutting was developed and belts and buckles began to carry ornate settings of native turquoise, prized for it's beautiful colors (a.k.a. "skystone") as well as intricate silverwork. From this unique, involved history has come a style of jewelry recognized worldwide as "American", thanks to the creative silversmithing of the Navajo and other Southwestern Indian people. Kiva offers belts in many styles, either linked metal or strung on heavy leather. The leather belts are often unpunched to allow the ultimate owner to personalize the fit.