Orb of the Moons

The Orbs of the Moons are ancient artifacts of unknown origin that allow their bearers to open red moongates by manipulating their placement. They appear in,  VI,  VII and  IX as well as in Savage Empire and Martian Dreams. Orbs of the Moons share some characteristics with moonstones, and are actually referred to as "moonstones" at times.

Age of Enlightenment
For positioning of the Orb in, see Orb of the Moons Locations An Orb of the Moons first appeared in, where such an artifact could be found secreted away in Lord British's Sandalwood Box. Eventually, the Avatar would bring this object to the lost monarch, who would use it to transport both himself and the Avatar's party from out of the great Dungeon Doom, where British had laid imprisoned. Upon his return, the king would then use the Orb to both return the hero to Earth and to exile his corrupt regent, Lord Blackthorn, to lands unknown.

Years later, as the Gargish race made its preparations to slaughter the False Prophet, a second Orb of the Moons appeared in the circle of stones behind the Avatar's house on Earth, as part of a trap devised by the gargoyles to ensnare the otherworldly hero. After a timely rescue by companions Iolo, Shamino, and Dupre from the place of sacrifice to which the Avatar was drawn, the reunited group managed to arrive in Castle Britannia, where explanations as to the use of the Orb would be received from Lord British, such that it might be employed for expedient travel throughout Britannia. At the end of this particular quest, after the Codex was sent at last to the Ethereal Void, a red moongate heralding the coming of Lord Draxinusom revealed the gargoyle king possessed such an Orb himself.

After the hero's return to Earth following Draxinusom and British's end of hostilities, the Avatar was approached by a friend, Dr. Elliot Archimedes Rafkin, who had heard of the Orb of the Moons and was curious to compare its properties to those of a large meteorite recently discovered in Central America. Experimentation with the meteor revealed that it appeared to be made out of the same substance as the Orb, and a botched test of electrical conductivity opened a warped cubic moongate to the temporally shifted valley of Eodon, where Rafkin and the Avatar would share numerous adventures. Back on Earth, after these events ran their course, the Avatar and Rafkin's associate, Dr. Spector, would receive from a red-haired woman a mysterious package purporting to be records of their travels circa 1895, which would instruct the pair as to manipulating an Orb of the Moons to produce a gateway through time. 

Age of Armageddon
Years later, in, the Avatar would fail to take the Orb of the Moons to Britannia after being summoned by the Time Lord's red moongate, leading Lord British to lend the hero his own Orb in the hope some kind of functionality could be yielded. Disturbances from the Sphere Generator, however, made use of the Orb and the moongates erratic, and gates summoned by the Orb would often repel the Avatar or even cause injury. On this occasion, the hero would eventually have need of the Orb to reach the captive Time Lord at the Shrine of Spirituality, as the dysfunctional blue moongates rendered travel to this destination otherwise impossible. With the destruction of the Sphere, all Orbs of the Moons ceased to function altogether, and Draxinusom's personal Orb shattered.

While the hero would not carry Lord British's Orb of the Moons while traveling to other worlds, the Avatar was eventually able to obtain a new Orb from the magician Nico, who offered it in exchange for rescuing him from a ritual sacrifice. In these last days of Britannia, however, the functioning of the Orb had been altered greatly, and it could only be used at the stone circles of the eight gates as a part of the Summon Moongate spell, in conjunction with the invocation of appropriate mantras.

Trinket
An Orb of the Moons came as a trinket with the original boxed release of, and each was unique in shape and any blemishes. Some of these trinkets are made of dark, translucent glass, while many are snowflake obsidian, which is opaque and exhibits characteristic grey flecks. As part of the Immortality Contest, however, some boxes contained a runestone in the Orb's stead.

Trivia

 * While it is never mentioned in the games themselves, Richard Garriott indicated that the Orbs of the Moons, as well as the moonstones, are formed out of blackrock in his interview with Caroline Spector for Ultima: The Avatar Adventures.
 * In Runes of Virtue II, the Orb of Moons sits atop the Lycaeum on Verity Isle. From there the hero can travel to any of Britannia's eight cities.