Sterling Silver Mojave Oval Blue Turquoise Ring Size 9 Kingman Mine Stamped 925

From an estate collection is this sterling silver Mojave blue turquoise ring.  Bezel set with an open back.  Blue color witha copper tone matrix.  Mojave turquoise is real turquoise bonded with a metal matrix, usually copper.  The oval stone measures approx. 10 x 12 mm.  The band is uniform size all the way around and measures approx. 2.8 mm in width.    The estate owner wrote on all her ring boxes the specifications of the item, as is seen in the photos.