Here is a pair of vintage Fred Harvey era turquoise and sterling silver kachina / yei earrings. Earrings like these can be seen in every Native American Indian jewelry history book.
Each earring measures 5/8 inch long and weighs 1 gram. I don't see a hallmark. Screw-backs. Excellent condition.
As is the case more often that not with the earlier Native American jewelry, these earrings is not marked for silver content or maker. However, I guarantee that they are coin silver (.900/90%) or sterling silver (.925/92.5%). When I test jewelry for silver content, I never drop the testing solution directly on the piece of jewelry since the acid could damage the piece. Rather I rub the piece against a testing stone and drop the acid on the testing stone.