Identification Stones, planks, papers

Many of the major cities have various means which the citizens of the city can prove their identity.
Many times, the items are magicked by whichever party is responsible for either tax collection or census.
The actual item or magic can take many forms, from a paper which accurately depicts the individual's likeness (much like an ID card), to gemstones which contained the person's information inscribed on the inside of the stone and the stone will only glow a certain color when in the hand of that individual.
Copying or forging such credentials usually has stiff fines and penalties. The easing of forging one of these items varies depending on the complexity of the process used in the item's creation, which in turn, often depends on the city or nation creating such an item.
Unlike the coin authentication shalingra, the verification process of detecting a forgery also depends on the individual city and usually requires a higher level spell.
Chrailis: Chrailis uses identification gems. Normally they are green like an emerald. However, when in the possession of the person they identify, the stone turns from green to blue like a sapphire. Inside the gem is the individual's full name and often times their rank if they have social standing. It can include also guild or military affiliation.
The process of gaining a stone takes roughly 15 GP and one must apply through one of the three Banks of Chrailis. After the application, the bank will do a brief background check to verify who the person is, often by questioning listed neighbors and acquaintances who are already citizens. Sometimes, additional charges may be required if the applicant will need the bank to dig deeper to find those who will vouch for them. One must live in Chrailis or it's surrounding lands no less than five years to gain secondary citizenship. Primary citizenship is granted only by the Aristocracy., though the banks still issue the stones. Additionally, stones can be changed or enhanced for new titles or name changes for nominal fees.
The other route of gaining a stone is upon birth. If one is born to a citizen mother in Chrailis, the bank will waive the fee to create the newborn their own stone. As such, most born in Chrailis from slave on up will already have an identification stone.
These stones are created in such a way that they are specifically attuned to their individual and that individual is attuned back to the stone. As such, one can not normally ever possess more than one working stone.