When it is created, a gemmanite ring is formed to be big enough to be placed over the finger of even the largest person. A person with Basic Earthlacing can tighten the ring onto the finger of a creature. Once tightened, there are only two ways to remove the ring. One is to use earthlacing to destroy or remove the ring. The other is to eat it, as gemmanite is an edible rock candy.
If left unchecked and exposed to air (gemmanite does not grow underwater), gemmanite will begin to grow over anything it is attached to. if unattended, a Medium size creature will become completely engulfed in gemmanite within 1d4 hours. For a Small creature, it will take 1d4-1 hours (minimum 1). Large or larger creatures can last for 1d6 hours before being completely engulfed.
As a creature is engulfed in gemmanite, it gradually loses more and more of its ability to move. When it is only the size of the ring, a creature is unaffected. As it gets closer to engulfing a creature (left to the DM's discretion), a creature will move through the incapacitated, grappled, restrained, and finally paralyzed conditions. A creature that is completely engulfed will eventually run out of air (again left to the DM's discretion, based on the growth rate of the gemmanite and the way in which it engulfs the player's body).