Eric is right. That is poorly refined wrought iron, and the way to fix it is to cut, fold, and weld several times, essentially refining it into better iron. You will need the hottest reducing atmosphere fire you can get and a lot of flux. This is where solid fuel outshines gas by a long shot, but it is still possible in gas if your forge is hot enough. My first real blacksmithing project in my first class I ever took in 1998 involved using some nasty old poorly refined iron bar (lintel bar from a fireplace in an old (ca. 1850) log cabin with family connections) to make a set of fireplace tools. One of the two instructors told me not to even try it, and the other told me how to fix it. When I was successful, he said "Now you can forge anything."