Originally rather plain, by the 1770s every surface of the rifle could have applied artwork. An accomplished gunsmith had to be a skilled blacksmith, whitesmith, wood carver, brass and silver founder, engraver, and wood finisher. European shops at the time had significant specialization of the trades, leading to separate tradesmen building each rifle. The American frontier had no such luxury, and quite often only one gunmaker would make the entire rifle, a process almost unheard of in 18th century trade practice. The flintlock action, with its spring mechanism, and single-action trigger, though, was often purchased in bulk by gunsmiths from England, and then fabricated with skill into an elaborate rifle. Early locks were imported but domestic manufacturing of locks increased in America among the more skilled gunsmiths in later years.