Stone of Sealing

Wondrous item, minor, very rare

This fist-sized, translucent green crystal contains traces of planar energy, and has the power to close and seal a permanent portal to another plane. In order to do so, the holder must also acquire a forked, metal rod worth at least 250 gp attuned to the same plane as the permanent portal. The holder must then place stone in contact with the fork and concentrate on it as though it were a spell for 1 minute. During this time, the holder must remain within 30 feet of the portal. Once this minute has passed, the portal closes in on itself and vanishes, leaving behind no trace of its prior existence.