Shattering this glass marble against a hard surface releases the short-lived portal within.
Wondrous Item 425,000 gp
Power (Teleportation) Consumable (Minor Action)
You create a portal in an adjacent square. The portal leads to a destination determined when the item was created. The portal remains open for 5 rounds, closing at the end of your turn on the fifth round.
The portal is misty, restricting vision to 5 squares into the destination. Until the portal closes, creatures can move freely between the portal and the location to which its connected.
Published in Manual of the Planes, page(s) 158.