In a medium mixing bowl, stir together all-purpose flour, whole wheat or rye flour, sugar, baking powder, orange peel, and salt. Using a pastry blender, cut in butter or margarine until mixture resembles coarse crumbs.
Stir in orange juice slowly while stirring, until mixture is moistened. Form into a ball.
On a well-floured surface, roll dough, half at a time, to 1/16 -inch thickness. Use a floured 2½-inch fluted, round cookie cutter to cut crackers. Prick each several times with a fork. Place on an ungreased baking sheet. Bake at 350° for 12 to 15 minutes or until golden.