Artifact 4, commit 10 (general)
A Hand of Rainbows resembles nothing so much as an elbow-length glove crafted of the finest chainmail, each link as delicate as that of a lady's fine necklace. The links are all made of orichalcum, diamond, ruby, topaz, emerald, sapphire, and amethyst, patterned to form an intricate swirling aurora of color over the glove's surface. No two Hands are patterned alike. Thin seams of moonsilver links down the palm, the arm, and the inside of the fingers let the glove size itself to fit an attuned owner's right hand.
These artifacts were mass-produced during the First Age, their sheer utility making them indispensable to the effects of any Celestial sorcerer worth his salt. To the Terrestrials, they were prized possessions, snapped up immediately when available. During the Usurpation, many of them were either lost or buried with their owners; their relative fragility (although each individual link is Essence-toughened, they can in fact be broken) made them easy casualties of the Solars' fall. The Shogunate, looking to replicate their power, eventually developed a similar artifact, but even at its height it could not duplicate the Solars' mastery.
The mechanics of this artifact are shamelessly stolen from Telgar's Whimsical Creation: "...By committing 10 motes of Essence to the Creation a sorceress gains 30 peripheral motes for the purpose of casting spells. Also, all Spell or Charm-based calculations treat her Essence score as if it were one higher. This higher Essence does not add motes to her pools, allow for higher trait maximums or help meet Charm requirements. The motes provided by the Whimsical Creation regenerate at the normal rate, which can not be increased by Manses or any other method. While wearing this artifact the sorceress is able to cast spells one turn faster then normal and is immune to casting disruption." It removes an additional Shape Sorcery action from casting time, as a houserule reduces the casting time by one action already. This allows instant casting of Terrestrial and Celestial spells as Speed 5 actions and of Solar spells after one Shape Sorcery action.
The Shogunate version, called Mela's Gesture, is a similar chain glove made from blue jade and emerald, without the moonsilver: it will fit its owner, but within a much more limited range of hand sizes. It provides the same 30-for-10 mote return and the same casting-time reduction and disruption immunity, but does not provide the Essence increase. Furthermore, its powers only function for Terrestrial Circle Sorcery. It is a 3-dot artifact.