Roll out two pie disks with the dough. Place one in the pan, cutting off the excess, cover and refrigerate for 30 minutes. Place the other disk in between sheets of plastic wrap and chill as well.
Preheat oven to 400ºF.
In a mixing bowl, combine the blueberries, sugar, cornstarch, salt, nutmeg, cinnamon and lemon juice. Mix well to combine.
Remove the pie dough from the fridge. Pour the blueberry mixture into the bottom crust, scraping the bowl clean to get all the spiced sugar mixture into the pie. Cover the blueberries with the other dough piece. Cut off the excess dough, and pinch the edges together, fluting as desired.
Cut four vents into the pie crust top using a sharp knife. Brush the entire pie with the beaten egg white, and then sprinkle with the sugar. Set the pie onto a baking sheet to catch the drips while baking.
Bake at 400ºF for 35 minutes. Reduce the heat to 350ºF, and bake for an additional 45 minutes, or until the filling is nice and bubbly, and the crust is golden brown.
Allow to cool for at least 1 hour before serving.