"Black Iron" is the term given to products made from mild steel, not to its colour. More robust than aluminium especially when baking at very high temperatures.
"Black Iron" pans should be seasoned before use. To Season: wash in warm, soapy water and quickly dry. Wipe a small amount of cooking oil on all surkaces and bake until the oil has burnt the pans. wipe all excess oil from the pan. "Black Iron" may need periodic re-seasoning. "Black Iron" will darken with repeated use . NEVER soak "Black Iron" in water.