From Chronicles of Blood Wiki
Gems fit into sockets to add benefits (or, at least, changes) to weapons and armor.
Gems come in four colors/types:
The jeweller in Club noir will be able to cut gems for you ... for a price.
All of the socket gems must be cut from a raw amethyst, emerald, sapphire, or dreadcrystal.
Amethysts, emeralds, and sapphires
These raw gems are occasionally dropped as loot by coven bosses once they have been successfully defeated.
Each boss has the ability to drop 1 of each type of gem in each loot drop.
The epic and legendary creatures at the summit of Mount Messmer can drop a raw dreadcrystal as loot.
Once a gem has been cut, it can be inserted into a socket on a weapon or piece of armor.
Replacing a gem
You can always put another gem into a full socket, but this will destroy the old gem.
- 28 November 2010: Pre-release details of the gems colors are leaked on the message board by Andi Huller.
- 6 December 2010: Gems are released in Chronicles of Blood.
- 13 February 2012: A fourth type of basic gem, the dreadcrystal is added to the game with the release of Mount Messmer.
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