Along with other cleaning methods, conservators often use air abrasion to clean the corrosion off metals and to reveal surface details on an artifact. With the air abrasion method, air and an abrasive are discharged through a tube onto any corrosion covering an artifact. The corrosion is worn away by means of friction. The abrasive can be anything from tiny glass beads to powdered walnut shell, and each varies in coarseness. Iron artifacts from the Dover Bridge site in Talbot County are only a few of the objects that have been treated by air abrasion at the MAC Lab recently. Dating to around 1700, these artifacts include axes, a hoe, knives, scissors, nails, a door lock, and a smoker’s companion.