trade in 2 (or other appropriate amount) major trait stones of each color to play…
have a bejeweled blitz type game that start with minors and has a limited amount of time to play (match 5 to add time)
can upgrade stones on a match 3 or more to next level (minor to major to runic to random arcane to celestial)
kingdom: 3 different possibilites come to mind based on story line
karkoth = because of magic - it takes alchemy/magic to make better stones
Khaziel = because of dwarves - dwarves are the consummate stone masters
or Adana = because it takes construction know how to combine them in new ways.