Whitestone
Trade Good, unknown (magic)
The sheer amount of leftover arcane power within the whitestone of the “Alabaster Sierra” mountains is incredibly receptive to enchantment. Magic items that incorporate at least an ounce of whitestone into their construction require only one-quarter the creation time of other magic items. Some alchemists in “Emon” have discovered that dissolving whitestone with specific acids can leave behind pure residuum, which can substitute for expensive spell components when such materials are not readily available.
Source: Tal’Dorei Campaign Setting Reborn p. 75