Masons might use a variety of instruments, but there are several tools that are common in any possible situation. First - and it's kind of a symbol for masonry - is a trowel. It's a hand tool with a handle and a metal blade shaped more like a shovel, that is used for spreading, smoothing and leveling concrete. Next up we have a taping knife, a tool used for a similar purpose - spreading compound on walls. Another important aspect is a mason's line - a firm, tear-resistant nylon or dacron wire, that is used to establish the level of your construction. Masons also employ a variety of scrapers, brushes, blades, and other tools to aid them while constructing various structures.