[https://nakamotoforestry.com/shou-sugi-ban/pika-pika/ Pika Pika] ( ぴかぴか ) is variant of charred cedar boards (焼杉板 or “yakisugi-ita”) used for siding in Japanese building. The charing helps preserve the boards. Pika Pika boards are scrapped with a wire brush that increases contrast by removing soot from softer grain in the wood.