What is the Grumpy Transmuter in the novel, Ambassador of the Shadows?

The Grumpy Transmuter is a creature from Bluxe that is able to manufacture more of any specific small item, such as pearls. Known as Grumpy, it represents Laureline's compassionate side, as seen in her concern for the creature after its reserves have been spent. It also symbolizes the power of currency because it is able to produce items that Laureline uses to buy information in her quest to find Valerian.