Gensokyo/Philosopher's Stone

''Not to be confused with the Philosopher's Stone, a vanilla accessory.

The Philosopher's Stone is a crafting station that can be purchased from the Curio Trader once a Tier 4 Boss has been defeated. The Philosopher's Stone allows the player to transmute metal bars into other types of metal, with the cost being based on the 'tier' of the metal being transmuted.
 * Transmuting metal to a higher-tier metal always produced one bar of the new metal. The amount of bars required varies, however:
 * Up to (and including) the transmutation of Gold Bar / Platinum Bar into Meteorite Bar: 2:1 ratio
 * Up to (and including) the transmutation of Adamantite Bar / Titanium Bar into Hallowed Bar: 3:1 ratio
 * Hallowed Bar to Chlorophyte Bar: 5:1 ratio
 * Chlorophyte Bar to Shroomite Bar or Spectre Bar: 3:1 ratio
 * Chlorophyte Bar to Luminite Bar: 7:1 ratio
 * Transmuting metals to a lower-tier metals is done with a ratio of 2:3.
 * The only exception is the transmutation of Shroomite or Spectre Bars into Chlorophyte, which has a 1:1 ratio.
 * Transmuting metals to their same-tier counterpart (e.g. Iron to Lead) always has a 1:1 ratio.

From 0.5.36.13 onwards, the Philosopher's Stone gates certain materials behind defeating bosses: The Mechanical Bosses must be defeated in order to convert Adamantite or Titanium into Hallowed Bars, Plantera must be killed to convert Chlorophyte into Shroomite or Spectre Bars, and The Moon Lord must be killed in order to convert Chlorophyte into Luminite Bars. This is to prevent sequence breaking by acquiring gear earlier than it can be obtained normally.