The spiritstone is acquired from Dizian in Purgatory when you complete the quest to leave Purgatory, and can also be obtained from Dizian in Nexus by saying "spiritstone" at any point to receive the base Spiritstone (below).
You can also upgrade these further by talking to Jecht in the nexus.
There is also a guy in Xiolia who will upgrade further if you say "Jecht sent me".
The 3rd upgrades are in Lamp.
The final upgrades are in the basement of Glimmer.
type of stones
Damage over time--Violent Spiritstone
Melee damage--Chartreuse Spiritstone
Direct spell damage--Crimson Spiritstone
Healing--Cerulean Spiritstone
Spiritstone #2 New Nexus Spiritsmith Jecht
Damage over time--one blue cherries, one fairy tear, and one white fur
Melee damage--one fairy tear, one white fur, and a sharp sentinel staff
Direct spell damage-- one fairy tear, one white fur, and an a S'aquia siren staff
Healing--one fairy tear, one white fur, and an enslaved efreeti bracer
Spiritstone #3 Xuolia Spiritsmith Quen
Damage over time--one snow griffon egg, a glass orb, and one gold bit
Melee damage--one snow griffon egg, a refined silver, and a ribcage shield
Direct spell damage--one snow griffon egg, a pure mana, and a crocolisk scale
Healing--one snow griffon egg, bottle of golden honey, and a depressing demon diamond
Spiritstone #4 Lamp Sabja Labt
Damage over time--blue pipe grass, a feather of phoenix, and watery amethyst
Melee damage--blue pipe grass, cackling emerald, and heart of magma golem
Direct spell damage--blue pipe grass, sash from a sorcerous efreeti, and motlen ruby
healing--blue pipe grass, effervescent sapphire, and talon of fleeing harpy
Spiritstone #5 Glimmer?
In Progress