The Ginzuishou, also known as the Silver Crystal or the Imperium Crystal, was the core power behind the Silver Millennium in the distant past, and the Crystal Millennium in the distant future. Created by a coven of mage-smiths on a small unnamed world in the shadow of the galaxy cauldron, the Ginzuishou is a substance that responds to and amplifies human will, making it a tool of unfathomable potential for good or for destruction.
The Ginzuishou was presented to the galactic capitol as a gift to Queen Selenos more than 85,000 years before the dawn of the modern era. It was also the only example of its creators' great work. Shortly after the Ginzuishou was presented, the mage-smiths who had created it were executed by forces loyal to Chaos. Having some inkling of what she had been handed, Selenos chose to spirit the crystal far away from the capitol world, allowing those loyal to Chaos believe it had been destroyed. The Ginzuishou remained hidden from the galactic eye for eons afterwards in the care of the Selenity dynasty-in-exile on Earth's moon, and was used with the utmost discretion and quiet until the dynasty was destroyed by the forces of Queen Beryl and the Metallia Force, at which point the crystal was lost again to history. Ten thousand years later, the Ginzuishou returned to the world as the legendary artifact wielded by Sailor Moon.
For years after the fall of Sailor Galaxia, the Ginzuishou continued to have an impact on the world. Not only did it send the inner senshi hurtling a thousand years into the future in the course of defeating Elios's great plot to destroy the senshi, its future iteration assisted Chibiusa in godmoding her way to survive the innumerable threats to her person.
It was not until the end of the Infinite Crisis of Suburban Senshi that the true depths of its power were seen as reality and time became increasingly distorted. Those parties not caught up in the battles discovered that Sailor Moon had actually not managed to redeem Sailor Galaxia, and what's more, had been fatally wounded in the course of their battle in 1994.
Rather than allow her world to be annihilated by Galaxia, Sailor Moon focused her will upon the powers of the ginzuishou and generated a new reality to supersede her own: one where she had redeemed Galaxia. Tsukino Usagi continued to live on in this new world, though it was only two fractions of her persona that lived onward: the naive, hopelessly optimistic American girl Serena, and the craving-dominated id aspect, Usagi, that would go on to become Neo-Queen Serenity in the first Suburban Senshi iteration of Crystal Tokyo.
So long as Sailor Moon maintained her concentration, this new universe would remain stable. However, her concentration was shaken when rei.bot and rei-bot exchanged a set of blows that rippled through all of time and space. Once shaken, Sailor Moon began losing control of the reality she had created, and the fabric of reality rapidly deteriorated. Had she lost complete control, the reality she created would have been supplanted by the endless rule of the Chaos-twisted Sailor Galaxia. Only through the intervention of the inhabitants of the Ten'ou House was Sailor Moon given a moment to rest and renew her focus, preserving reality as we know it.
The power of the ginzuishou, however, was something that the ascendant rei-bot felt was inimical to the growth of humanity. Rather than allow the Serenity Dynasty to rule by fiat in centuries to come, she utterly destroyed the ginzuishou with her own power, along with numerous other artifacts of great strength. With the ginzuishou annihilated and the knowledge of how to create it lost to the deep fathoms of time, the book seemed to be closed on this part of history.
To the surprise of many, however, Tsukino Usagi returned to prominence in 2011, armed with the Ginzuishou. The id-driven Usagi used its reality-rewriting power to reward her sycophants and punish her detractors, and it remains her most potent defense against the Suburban Senshi who seek to end her short-sighted reign of terror.