A timepiece component comprising a dry, self-lubricating surface layer, consisting entirely of boric acid, having a thickness of 50 nanometres to 1 micrometre. A method for coating a timepiece component with a self-lubricating surface layer, including dissolving, at ambient temperature, boric acid H3BO3 granules or powder in a solvent chosen from among water, isopropanol, propanol, methanol, methyl propanol, glycol ethylene, glycerol, acetone, in a proportion of 0.01% to 1.0% by mass; mixing and agitating the solution; dipping the component to be coated in this solution; removing the component from the solution and allowing the liquid phase to evaporate, with the surface forming the surface layer kept away from any foreign bodies, until evaporation is complete; and repeating the dipping and evaporation steps until the desired layer thickness is obtained, from 10 nanometres to 1 micrometer, or more particularly from 50 nanometres to 1 micrometre.