The average weight of an adult human tooth varies, but it typically ranges between 0.5 to 1.5 grams. This variation in weight depends on several factors, including the type of tooth (molar, premolar, canine, incisor), the individual's dental anatomy, and the composition of the tooth (enamel, dentine, pulp, cementum). Molars, being larger, tend to weigh more than incisors or canines.