I've also thought over the years I'd like to do one of these with black fabric! uses sooo much fabric though. I've used kona black and in one swap I can tell the blacks were different - each person swore they used that color but some looked brownish next to other blocks and someone said they dye over other colors for the black..not sure if that's true but seems like the stuff frayed - not sure how it would be to handsew the windows. I love moda marble's jet black - dimples (if they still make that line) had a nice dark black but it frayed pretty badly when I was strip piecing and paper piecing - like the fabric though.