Catalhoyuk, one of the earliest cities, inhabited from 7,500 B.C.E. to 5,700 B.C.E., was a center for the obsidian trade. The volcanic glass was used to make knives, razors, and mirrors. It seems trade in luxury items like razors may well have led to civilization.
Speaking of luxury items used in grooming, tweezers date from the stone-age, when they were carved from clam shells. By 3,000 B.C. E., Egyptians were using a metal variety nearly indistinguishable from today's tweezers. The word tweezers originates from the Old French word Etui, which was a small case used to carry a variety of grooming aids.