Palantirs can be used to communicate across both Space and Time
There are believed to be 9 Palantirs and they have an alignment (Law vs Chaos/Good vs Evil) as well as being linked to gates
Palantirs were created by Lastar to control the Pentagram Gates (not the natural portals) and lock them to their host dwarrowdelfs. Some of the Palantirs were formed using material from the natural portals.
Every Palantir thus has a natural planar alignment but this is not immediately obvious.
It was the act of removing the Palantirs from their host dwarrodelfs that caused the gates to become unlocked
Current ownership of Palantirs:
Created by Orodruin for Lastar to control the gates that Lastar knew about: Air; Earth; Fire; Water; Ethereal; Astral x 3 (Vikrain; Efferendil; Maedus)
1 - Astral (Maedus) - Orcus (taken from Fremar the Norseman when Gos fell?)
2 - Astral (Efferendil) - Malenwe in Walorin's House
3 - Astral (Vikrain) - Inwe definitely has one but don't know which
4 - Ethereal - LN - Yishmay (was Balfor's? Found by us in Olga) - (from Lan Zi)
5 - Prime - Gwendolyn had one when she fled Sutur - where is it now (need to ask her!)? Possibly Malek? <- Morwath saw it there
6 - Earth (Aarda) - Demogorgon
7 - Fire - NE - Lan Zi Bao (Morgul en route to Maedus - reclaimed it from Lord Marin)
8 - Water - LE - Takeda (from Lan Zi Bao)
9 - Air - Enrodire has one but don't know which
Perion had one at one point?
Fremar (Norseman) had a palantir (from Maedus - now with Orcus?) and used it to speak with Perion.
Perion's palantir was delivered to Gos by Bavarik himself in the 2nd Age - see above re Fremar. Not clear where Bavarik got it from (it could be the original Sutur palantir?)
Rantor/Tuar Chan had one but we took it
While in Morgul we left one in the care of Lord Marin but not clear if we took it back or left it with him. If we took it back then Morwath may have one?
Lastar set up his pentagrams after the swap between fire and water the Drow had brought about; the palantirs should match the original pentagrams:
Air - Emras; Zem (living in Minas Emras) receives the blue Ring of Air.
Earth - Aarda; Hamar (living in Minas Aarda) receives the green Ring of Earth.
Fire - Tiris; Dor (living in Minas Tiris) receives the indigo Ring of Water.
Water - Morgul; Ishtur (living in Minas Morgul) receives the red Ring of Fire.
Astral - Maedus
Ethereal - Olga
Negative - Zundar
Positive - Blaven's Pool
Sutur - Control/Prime
Some relevant history
The Palantirs. Lastar creates the scrying stones so that his armies would not be surprised again. As Lastar retakes the land, they are placed as follows: Minas Tiris, Morgul, Maedus, Emras, Aarda and Bolgar and Sutur. (1st Age History)