Focus Core

A focus core makes up a focus along with an inscription.

there are 4 focus cores in the PvP Equipment window.
 * Health +30
 * Health +45 (while enchanted)
 * Halves casting time of spells (chance 10%)
 * Halves casting time of spells of item's attribute (chance 20%)

Salvaged items in PvE also include:
 * Focus Core of Aptitude - Halves casting time of spells of item's attribute 10%..20%
 * Focus Core of Fortitude - Health +15...+30
 * Focus Core of Valor - Health +45...+60 (while hexed)
 * Focus Core of Endurance - Health +30...+45 (while in a stance)

after choosing the item, the focus core and the inscription, press create and you will have item with focus core.