Gundanium is created through the most advance refining, fusing and deoxidizing techniques, which are only possible in space. The complex formula was first called GND, short for Genetic on Universal Neutrally Different Alloy. Later, the suffix "-nium" was added to distinguish that alloy from other similar alloys that were being developed on Earth. Gundanium was still superior to the competition because of its zero-G creative process.
One of the central elements of Gundam Wing's mobile suits is the use of Gundanium Alloy. What makes Gundanium so incredible is its properties: it is practically immutable, highly heat-resistant, and electrically neutral. These properties combine to produce a material that is extremely hard to damage, lending to the Gundams' atmosphere of invincibility and intimidation. Additionally, heat and beam weapons produced using Gundanium are much stronger than similar weapons made using traditional titanium, thanks to its extremely high melting point allowing it to produce hotter and therefore stronger beam energy. Gundanium is very rare and hard to make, since it requires the use of super-heated plasma and nanomachines, and very few people know exactly how to make and refine it. Further, it is said that Gundanium can only be produced at Lagrange points under zero-gravity conditions, putting a very powerful tool in the hands of the colonial rebels. To a certain extent gundanium served as a character shield that kept mobile suits with important characters in them from being completely destroyed. Prime examples include when Trowa was in the OZ-13MSX1 Vayeate and it survived a shot from XXXG-00W0 Wing Gundam Zero buster rifle without being completely vaporized, despite the fact that that weapon was capable of reducing entire space colonies to clouds of debris. Another example is when Wing Gundam (used by Lady Une at the time) was blasted with the battleship Libra's main cannon. Although the Gundam was heavily damaged with its lower torso blown off and rendered inoperable, Une was uninjured.
There is a common misconception that Gundanium is nigh-invincible; this has been disproven by several instances in Gundam Wing and Endless Waltz where the Gundams were damaged, usually by beam weapons. However, this has also led to the supposition that Gundanium is especially strong against solid weapons, like traditional machine guns (as is the similar alloy Gundarium, from the Universal Century). This second theory may have some truth to it: according to the novelization of Gundam Wing, a physical impact roughly equal to the force of a train travelling at 120 kilometers per hour while towing ten-plus transport cars would be enough to easily destroy Gundanium. This is also covered in the series where Heero attempts to destroy the Wing Gundam with three naval torpedoes detonated simultaneously, although no exact figures are quoted and Heero was apparently trying to activate the Gundam's disarmed self-detonation device.
Gundanium's name is actually an acronym; it stands for Genetic on Universal Neutrally Different Alloy. The suffix -nium was added to distinguish it from similar alloys being made on Earth. In the After Colony Universe, the word "Gundam" is derived from this acronym (GUNDAnium Mobile suit). Despite this fact, not every mobile suit made with Gundanium is a Gundam (examples: Vayeate, Mercurius).
In an Easter Egg of the Series, Gundanium is referred to as "Gundarium Theta" which would make it an eighth-generation descendant of the Lunar Titanium used on the original RX-78-2 Gundam of the Universal Century, although the two series are canonically unrelated.
Use in MS Production
Some intelligence indicates that OZ scientists experimented with using Gundanium alloy in MS creation. The very existence of Gundanium was kept secret, perhaps because it was a possible secret weapon for OZ. The five scientists who left the Tallgeese project took with them the knowledge of Gundanium, allowing them to create the Gundams that would later be the bane of OZ.
The creation of the Gundams took decades of work behind closed doors, due in part to the slow process of manufacturing Gundanium. This is evidence of just how long a process Operation Meteor was, with the Gundams being created before their eventual pilots were even born.