It doesn't necessarily have to be Ayam Cemani mix. We have Easter eggers that are fibro skinned and there's no Ayam Cemani in them. Kinda makes ya wonder who has him cause I've sold chicks out of our stock at auctions several years ago.
My mom got it from her grandmother and recently gave it to me with the condition that I would use it. She didn't use it and regrets that she has no really good memories of enjoying it.