Gold Dust

, is the name of the weapon used by the Fourth Kazekage. Due to the conductive properties of gold, an alternating magnetic field can induce a current in it, which generates its own magnetic field, therefore small particles of it could be manipulated in a similar manner to that of the sand utilised by Shukaku's jinchūriki, through the Kazekage's Magnet Release kekkei genkai. When he utilised this ability, dark rings appeared around his eyes that resembled the permanent ones around those of his youngest son Gaara.

In sufficient quantities, this sand gold could be fashioned into a diverse range of forms, which the Fourth Kazekage employed to assault opponents and intercept hostile attacks. By constructing more complex structures, he could use it to perform even more intricate tasks, such as observing an area from afar with the Third Eye.

In the past, this weapon was instrumental to the protection of Sunagakure during the Fourth Kazekage's tenure, by allowing him to effectively subdue Shukaku each time the beast went berserk. This was accomplished by layering his sand gold atop of the sand controlled by the beast. As gold is heavier than sand, it made it more difficult for the creature to manipulate, thus slowing if not stopping the sand's movement entirely.

When confronting the Second Mizukage, Gaara incorporated some of his father's gold dust into his own sand in order to both cool and weigh down the Mizukage's exploding clone, after the clone's own heat fused the gold onto its body.

Trivia

 * Gold isn't a magnetic metal like iron, nickel or cobalt. Although it is diamagnetic, this effect is orders of magnitude weaker. The jutsu induces a current in the gold, to give it magnetism.
 * Gold is approximately 7.3 times denser than silica, the main component of sand; and about 3.7 times denser than magnetite, the main component of Iron Sand.
 * The different magnetic behaviours allow gold dust, sand and magnetite to be separated from one another.
 * When Sunagakure was facing dire economic strains, this gold dust was used as a valuable trade commodity of the village.