Preheat the oven to 425 F (205 C).
Mix the flour, sugar, baking soda, baking powder, tea and lemon zest in a large bowl.
Add the butter and incorporate it into the dry ingredients using a pastry blender.
Add the raisins and nuts, reserving 2 tablespoons of each for the finishing touch.
Mix in the buttermilk using a fork.

Form a ball with the dough and knead for 2 minutes on a lightly floured surface.

Roll out the dough to a thickness of 1/2 ” (1.25 cm).
Using a pizza cutter, cut out 8 triangles.
Place them on a baking sheet lined with a silicone mat.
Brush the surface of the triangles with the tablespoon of buttermilk, then top with the reserved raisins and nuts.

Bake in the center of the oven for 15 minutes or until the scones are golden brown.
Serve with butter and jam.