[25] Maybe, the ‘Blake balle of Flaundres’ (‘black balls of Flandres’) mentioned in an anonymous recipe of the 15th century refer to coal of that region? Anonymous, BL MS Sloane 963 (#1854), in Clarke, The crafte of lymmyng and the maner of steynyng: middle english recipes for painters, stainers, scribes, and illuminators, p. 246, [§C5].