USA three RPPC photo postcards (Aboriginals?)

Three early RPPC photo postcards. Assuming USA. Appear to be of aboriginal origin.

• 1904-1918 4 men and 2 women, worksite?  Some smudges on back
• 1910-1930 Mother and child. Staining/`toning on back. Creases LL/LR corners
• Date? Two young women names on back “May Tanner  Lena Priest” (?) Multiple deep creases/folds. Large toning marks on back