In a large bowl, mix together the flour, sugar, baking powder, baking soda, and salt. Dice the butter into small squares and work into the flour with fingertips or a pastry cutter until the mixture resembles coarse meal and the butter bits are the size of rice grains. Stir in the lemon zest and raspberries, being careful not to break the berries too much.

In a small bowl, whisk together the buttermilk, egg yolk, and vanilla. Pour over the dry ingredients and mix with a spatula until just combined to form a moist dough. Turn the dough out onto a floured surface and form into a ball. With your hands, flatten the dough ball into an 8-inch round and cut into 8 wedges with a sharp knife. Transfer the wedges onto a parchment lined baking sheet, spacing them 2 inches apart.

Brush the scones with the remaining egg white and sprinkle with raw sugar. Bake for 17-20 minutes, until nicely browned and a toothpick inserted in the center of a scone comes out clean.

To make the icing, whisk the lemon juice and powdered sugar in a small bowl. Once the scones are cool, drizzle the glaze on top.