Portkey

Invented by the Arcanist Guild of Menetar, a portkey functions as a battery of concentrated arcane energy that powers the arcane inscriptions which activate a planeport or other interplanar gateway. The portkey is typically made of a gemstone enchanted with a specialized spell which contains the necessary arcane energy as well as the coordinates for the planeport's destination. However portkeys have been known to be made from other materials, such as actual keys made of silver or even magical weapons.