In a bowl, mix flour, salt, baking soda, and cream of tartar.

Stir the dry ingredients thoroughly.

Rub the butter into the dry ingredients with your fingers until the mixture resembles breadcrumbs.

Gradually stir the beaten egg and buttermilk into the flour mixture to form a dough.

If the dough is too moist and sticks to your hands, add a bit of flour until it's manageable.

Turn the dough onto a lightly floured work surface and knead as little as possible to form a soft, pliable dough ball.

Divide the dough into 2 equal parts.

Flatten each part with your knuckles into a round disc about 6 inches in diameter and 1/2 inch thick.

Prick each disc about a dozen times with a fork.

Cut each disc into four sections.

Place the scones on a lightly greased baking sheet.

Bake in a preheated oven at 375F (190C) for about 15 minutes, or until golden brown.

Optionally, add 1/2 cup raisins or currants to the dough before baking.

Serve the warm scones with butter or jam if desired.