Instead of your usual rainbow,  imagine a rainbow of warm sensual colors:  burgundy-red golds, browns and tans.  That’s rainbow jasper.   Like all jasper its deeply banded colors come from organic material and iron oxides imbedded in it.   Rainbow jasper is found in Africa and India, but it reminds me of the jasper found in southwest Colorado where the Anasazi, famous for their cliff dwellings at Mesa Verde, formed arrowheads from it.   Today, with the fashion world’s shift from sky tones to earth tones, this unusual jasper is used more widely in jewelry than ever.  Rainbow jasper helps us focus without overanalyzing things.   The is 17 1/2 inches in length and closes with a silver swivel lobster clasp.