A palantir in the New Line film
Seven seeing-stones of Gondor and Arnor used as a communication system between the different forces of good. Looking through one of the palantiri, someone could see somebody else at the other end in a completely different place in Middle-Earth. They were smooth spheres that varied in size. They were generally the size of a palm of a hand, for hands were used to summon the person on the other end to a palantir. The palantiri were made by Feanor in the Years of the Trees. This happened in the Undying Lands. They were shipped to Middle-Earth later on. The seven stone were the Stone of Osgilisath (chief stone), The Stone of Elendil, The Stone of Amon Sul, The Stone of Annuminas, The Stone of Orthanc, The Ithil-Stone, and the Arnor-Stone. The Stones were very powerful and dangerous and at the loss of The Stone of Osgiliath, the other stones began to fall into decay. When the Ithil-Stone was taken by Sauron, contact was available between he and his future ally Saruman.