Preheat oven to 400 degrees F. Greased a baking sheet.
In a large bowl combine the flour, sugar, baking powder, baking soda, salt, and orange zest. Cut in the butter with a fork or a pastry cutter. Toss in the mini chocolate chips
In another bowl combine the egg, orange juice, and milk. Pour the wet ingredients into the dry ingredients. Mix by hand just until ingredients are combined. Form into a ball.
On a floured surface form the ball into an 8-inch circle. Cut into 8 wedges. Place on the prepared baking sheet. Bake the scones for about 15 minutes or until the edges start to turn a light brown.
Cool on a cooling rack.
As the scones are cooling. Mix together the powdered sugar, orange zest, and orange juice. Beat until smooth. Drizzle over cooled scones.