<span class="SFPTagline"> From SCIFIPEDIA </span>

Naquadah (also known as naqadah) is a fictional heavy metal in the TV series Stargate SG-1. The nameless mineral was first hinted at in the movie Stargate, where Ra used it to enhance a nuclear weapon, increasing its explosive power. Naquadah also powered the sarcophagus that provided Ra with immortality. The mineral from the movie was given a name and expanded use in the TV series. It is the material from which the Stargates are made.

Naquadah is an extremely valuable substance, with unusual properties and a wide array of uses. It has been used in several Ancient technologies and is the power source for the great majority of Goa'uld technologies. Naquadah is rare and not natural to Earth but occurs naturally on many other planets throughout the galaxy. The Goa'uld took humans from Earth as slaves for the purpose of mining naquadah on other planets. Refined, weapons-grade naquadah is also the desired currency among the Lucian Alliance.

Variations on naquadah include:

• Liquid Naquadah—Used to power Goa'uld staff weapons. O'Neill used the liquid naquadah cell from a Goa'uld staff weapon to power a small power generator he designed using the Ancient knowledge downloaded into his mind in the episode "The Fifth Race."
• Weapons-Grade Naquadah—A rare, refined version of the metal.
• Naquadria—A very unstable variation discovered on Langara. Naquadria is more explosive and potentially more powerful than naquadah. The Tau'ri attempted to use naquadria to power the X-302's hyperdrive engines, but it proved too unstable. They've also developed naquadria-enhanced nuclear bombs designed to destroy Stargates. This device is known as the Mark IX "Gatebuster". Long-term exposure to naquadria radiation can result in brain damage with the victims showing symptoms of schizophrenia.

Goa'uld symbiotes have naquadah in their bodies. It is passed on to their hosts, and remains in the bloodstream of the host even after the death of the symbiote. The presence of naquadah in the bloodstream is the key to using some Goa'uld technology, including the Goa'uld hand device and the ribbon device. It also allows control of a Ha'tak.

Humans who have been taken as hosts are able to detect the presence of naquadah in others. Hathor was drawn to the Stargate and knew its location because of its makeup.

In the episode "Learning Curve," Carter is taught how to make a Naquadah Generator. Since then, the process has been refined and made more powerful. Reactors have been designed and used to help power the Ancient Control Chair in Atlantis and Antartica.

Naquadah reacts violently with potassium, as seen in the episode "Singularity," in which Cassandra is used as a human weapon. She is implanted with a biochemical bomb that would trigger when she went through the gate, and the naquadah and potassium combined with each other.