Below is a guide on what loot the treasure chests contain and where they can be found in the Thunderbolt Palace in Atelier Sophie 2!
Thunderhead Gate
3200 Cole
Plasmein
Thunderclap Garden
Wurzel Aqua
Storm Bracelets
Diamant Gemstone
Thunderstorm Chapel
2500 Cole
Herbal Sky Medicine
Alchemy Mantle
Sparkling Sand
Golden Leaf
Thunderstrike Hall
Eternal Breeze
Dreamer’s Tentacle
4000 Cole
Eternal Plate