Gemstone Mines
From Jenny Everywhere Wiki
The Gemstone Mines were apparently mines under the control of the Crew of the Copper-Colored Cupids, possibly being the origin of their very Gemstone Hearts.
When he believed that his recklessness in attempting to romanticise Madame Tarsa had allowed her to gain possession of the formula to the Cupids' Love Potion, Larrikin-1029 fretted that when they learned about this, the Cupid Parliament would punish him with forced labour in the Gemstone Mines. In the end, this doomsaying was never tested as Larrikin successfully destroyed Tarsa's ersatz-Potion sample and all her notes. (PROSE: The Toymaker's Labyrinth)