Considering helping out on the wiki to keep it updated - in particular the changed unique items need to be updated to reflect 2.6.0 changes.
Mods and base items have been updated to 2.6 values - skill progressions on some skill gem pages may need updating or some bugs need to be fixed.
Gemcutter's Prisms are a rare item that can be obtained from slain enemies or found in an Artisan's Strongbox.
One can sell a gem with 20% quality to any vendor for a Gemcutter's Prism.
One can sell any number of gems whose total quality is at least 40% to any vendor for a Gemcutter's Prism.
- A set of 5 Emperor's LuckEmperor's Luck55× CurrencyThe house always wins.1 can be exchanged for five Gemcutter's Prisms.
- A set of 3 The GemcutterThe Gemcutter3Gemcutter's Prism"In the hands of a master craftsman, a worthless pebble can adorn the crown of a king." can be exchanged for a Gemcutter's Prism.
- A set of 7 The UnionThe Union710× Gemcutter's PrismOn the 21st of Eterni,
two become one,
their light outshines
the setting sun. can be exchanged for ten Gemcutter's Prisms.
1Not guaranteed (set grants 5 of any random currency)
Because Gemcutter's Prisms are relatively rare, it is not advised to apply them to gems that have little or no quality. However, selling a Gemcutter's Prism along with a level 20 gem to any vendor will give you a 20% quality, level 1 version of that same gem. Because it is possible to level many gems at once, it is generally considered a cost-efficient method of obtaining 20% quality gems if the player does not have the means to obtain a large number of Gemcutter's Prisms.