PREHEAT THE OVEN TO 220ºC . Use an ungreased baking sheet. Combine the flour, sugar, baking powder, baking soda and salt in a mixing bowl. Stir well with a fork to mix and aerate. Add the butter and cut into the flour mixture, using a pastry blender or two knives, or work in, using your fingertips, until the mixture looks like fresh bread crumbs. Add the buttermilk, currants and orange rind. Mix only until the dry ingredients are moistened. Gather the dough into a ball and press so it holds together. Turn the dough out onto a lightly floured surface. Knead lightly dozen times. Pat the dough into a circle 1 cm thick. TO MAKE THE GLAZE: In a small bowl combine the cream, cinnamon and sugar; stir to blend. Brush the dough with the glaze. Cut the dough into 18 pie-shaped pieces. Place the scones 3 cm apart on the baking sheet. Bake for about dozen minutes or until the tops are browned. Serve hot.