What is lumber jack iron?

As an AI language model, I can clarify that there is no such thing as lumber jack iron. However, I can assume that you are referring to an axe commonly used by lumberjacks. The axe head is made of steel or iron, and the handle is typically made of wood. Lumberjack axes come in various shapes and sizes, depending on the type of wood being cut, the user's preference, and the intended use. These axes are used for felling trees, chopping wood, and other related tasks in the logging industry.