Whisk the egg, milk, and cream together and set aside.
Combine the flours, cornmeal, sugar, baking powder and salt.
Add the butter, coarsely chopped. Work the butter into the flour mixture leaving some clumps slightly larger others.
Slowly add the milk mixture until the dry mixture is just wet. The dough should be rough and sticky, but hold together in a ball when lightly kneaded. If it is too wet, add a bit more all purpose flour.
Turn the dough out onto a lightly floured surface and shape it so it is about 3/4 inch thick. Cut the dough into equal sized pieces and form the scones.
Place on a parchment lined baking sheet, and refrigerate until ready to bake.
Preheat the oven to 425F Brush the tops of each scone with a bit of milk, and sprinkle with a bit of raw sugar if desired.
Bake for 12 to 15 minutes, or until the tops are golden brown. Cool on a wire rack, and serve immediately.