Combine first 6 ingredients; cut in butter with a pastry blender until mixture is crumbly. Add buttermilk and dried cranberries, stirring just until moistened.
Turn dough out onto a lightly floured surface; knead 5 or 6 times. Pat into an 8-inch circle. Cut into 8 wedges, and place 1 inch apart on a lightly greased baking sheet. Brush with milk, and sprinkle with 1 tablespoon sugar.
Bake at 425° for 15 minutes or until scones are golden brown.