The scales sit on a spiral whose angle comes from the same series as a real cone. Each layer is slightly larger than the one below, and the shape follows from exactly that — it was never drawn.
What ships is the shade without electrics, with a prepared opening for a standard E27 pendant. There is a practical reason: the moment electrics are included, a wooden object becomes an electrical appliance with its own certification requirements.
Birch, stained or natural. Ships flat, assembly takes about twenty minutes with the enclosed instructions.