The official GemStone IV encyclopedia.
Constitution crystals can be made by empaths via the Trinkets subskill of Alchemy.
The crystals can be rubbed to increase the user's Constitution bonus. Each completed formula will yield three uses.
The use of the constitution crystals is restricted by both level and by time since last use.
Lesser constitution crystal
A lesser constitution crystal provides a bonus of 5 to constitution. Characters must be at least level 30.
Greater constitution crystal
A greater constitution crystal provides a bonus of 10 to constitution. Characters must be at least level 60.