This is something addressed by your local codes. Some states (Oregon) have state-issued cards, while other places (Reno) have them issued by the city.
I worked for years with the local inspector carefully not "seeing" me work. Finally, one day, he asked to see my card. He almost fainted (from shock) when I produced one; it seems it has been rare in his experience for someone to get the card before they're first 'caught!'
Any apprenticeship program ought to issue some sort of "card" or "diploma" that attests to your completing your work. I would ba amazed if an electrical contractor hired a "journeyman" without asking to see this paper.
