The Crystalline Sword is one of the more unique-looking swords in the game. It is very rare, and very sought after. Perfect versions are among the most highly prized items available in Guild Wars, and can sell for millions of gold pieces in an auction. The blade is made of a piece of thin, translucent crystal.
Purple Crystalline Swords are rather rare. These drop from quest reward chests in the Underworld, Sorrow's Furnace, and the Fissure of Woe . Gold Crystalline Swords only drop in the Hall of Heroes and Underworld hard mode reward chest and now in Zaishen Chest too, and are rare.
Applying dye to this sword affects the hilt (the gold part of the sword in the image). It also seems to make the color of the dye appear a little brighter or off-tint (such as a yellow being a bright, slightly green color), when coloring the shaft in one color, the blade gets the inverted color in the storage mini image.