Stack of three rings, can be worn separately or stacked together on one finger.
Personally purchased from a jewelry store in Gallup NM, owner explained that these rings were vintage from the 1960's, and Native American Navajo made (although clearly hand cast). 
These cuties had been sitting in a forgotten drawer behind the jewelry counter for a long, long time. How fun!
Heart is malachite
Butterfly is turquoise
Square is mother of pearl
Sterling silver (tested)