Preheat the oven to 400 degrees F.
Combine the flour, baking powder, salt, and sugar and gently whisk together. Add the grated cold butter to the dry mixture and toss to combine so the butter is evenly distributed.
Fold the blueberries and lemon zest into the dry mixture. Make a well in the center and pour in the heavy cream. Fold everything together just to incorporate; do not overwork the dough.
Form 12 medium sized mounds out of the dough. The size can vary depending on if you want to stretch the recipe to make more. Arrange them on a parchment lined baking sheet and bake in the pre-heated oven for 16-20 minutes, or until the top just barely turned golden brown.
Combine the lemon juice, powdered sugar and melted butter in a small bowl and whisk until no clumps remain. Once the scones have cooled, drizzle with the glaze and let cool.