Mastery vs Specialization
Specialization points are obtained by creating items, gathering resources or using specific pieces of gear. Unlike Mastery points, specialization points are specific to an item or skill (e.g Great Frost Staff Combat Specialist or Poison Brewer) instead of a general tree, such as Frost Mage or Alchemist.
Gathering specialization points are obtained by gathering resources of the same Tier as the specialization level. Each gathering specialization increases gathering yield by 0.5%, gathering speed modifier by 0.5, and +0.2 item power for the Gathering Gear of that skill's tier.
Production specialization points are obtained by Crafting or Refining. Each specialization point provides a +30 bonus to focus efficiency while crafting or refining under the same Mastery, and +250 efficiency when crafting or refining a specific product.
Weapon and Armor Specializations
Weapon and armor specialization points are obtained through fame farming. Each piece of gear the player is wearing while killing mobs is given the fame the mob is worth. Each specialization level gives +2 Item Power for that skill and +0.2 Item Power for all other items of the same Mastery. At 100/100 specialization, the player will have +198 Item Power for that gear piece and +20 to other gear of the same Mastery.
Example: If you use Galatine Swords and gain up to 100/100 you will have +200 extra item power to its base item power (IP).
However, every tree of Spec. gives +0.2 x Level of Specialization on all items from the same tree.
Example: If you use Galatine Swords and you have 100 on the Base Swords tree, and 100 on all 4 kinds of swords (Artifact Sword, Dual Sword, Claymore, and Broadsword) you will reach the so-called MAX-SPEC, that will increase with +120 extra Item Power to the base Item Power to every single sword you use.
Here is an example of how a 100/100 Spec looks: