![Why is cast iron black on the outside and when you sand it turns metal color? What is the black stuff made of? : r/askscience Why is cast iron black on the outside and when you sand it turns metal color? What is the black stuff made of? : r/askscience](http://i.imgur.com/qPYsCCo.png)
Why is cast iron black on the outside and when you sand it turns metal color? What is the black stuff made of? : r/askscience
![Amazon.com: Mirro MIR-19053 12" Pre-Seasoned Ready to Use Round Cast Iron Skillet with Helper Handle, Black: Home & Kitchen Amazon.com: Mirro MIR-19053 12" Pre-Seasoned Ready to Use Round Cast Iron Skillet with Helper Handle, Black: Home & Kitchen](https://m.media-amazon.com/images/I/71tQkp+uB8L.jpg)
Amazon.com: Mirro MIR-19053 12" Pre-Seasoned Ready to Use Round Cast Iron Skillet with Helper Handle, Black: Home & Kitchen
![Amazon.com: Lodge 10 Inch Cast Iron Chef Skillet. Pre-Seasoned Cast Iron Pan with Sloped Edges for Sautes and Stir Fry.: Cast Iron Skillet: Home & Kitchen Amazon.com: Lodge 10 Inch Cast Iron Chef Skillet. Pre-Seasoned Cast Iron Pan with Sloped Edges for Sautes and Stir Fry.: Cast Iron Skillet: Home & Kitchen](https://m.media-amazon.com/images/I/71NwXbY+6nL._AC_UF894,1000_QL80_.jpg)