American turquoise 
Kanaga by Tuareg master.
3” long
2” wide
Turquoise is 1” side.
The creator god Amma: The vertical and horizontal crossbars of the mask are said to represent the arms and legs of the supreme creator god, Amma. A dancer wearing the mask rotates and moves it, symbolizing Amma's creative force bringing life into the world.
The universe: The kanaga also illustrates the structure of the cosmos. The top crossbar represents the heavens, while the bottom one symbolizes the earth.