Place currants in a small bowl and fill with warm water to cover. Let sit for at least 15 minutes. Drain and set aside.
Using an electric mixer on low speed, combine 4 cups flour, the baking powder, 1/4 cup sugar, the salt and the better until the mixture resembles a coarse meal. Add the cream and 4 eggs. Mix just until blended. The dough will be slightly sticky. Fold in the drained currants, cover with plastic wrap and refrigerate for 1 hour.
Preheat the oven to 450 degrees.
Line a baking sheet with greased parchment or wax paper. On a lightly floured surface, knead the dough gently for 1 minute, adding flour as necessary to achieve a smooth consistency. Pat to a thickness of about 3/4 inch.
Cut into rounds with a 2 inch biscuit cutter and place on the prepared baking sheet.
Lightly beat the remaining egg and brush over the tops of the scones. Sprinkle with remaining 1/4 cup sugar.
Place in the preheated oven and bake for about 15 minutes, or until golden brown.
Serve hot with sweet butter, raspberry preserves, lemon curd or fresh whipped cream.