Raw materials are harvested on different fields. At the collection area, a merchant NPC can usually be found to sell the tools required, and may also refine 20 raw materials into one refined material. Some maps may have an Apprentice Refiner or a Master Refiner instead.
Note that a handful of raw materials are needed for the Eversun Elder and the Darkdale Elder's missions, and some of the refined materials are required to upgrade weapons (e.g. an Apple Wood to upgrade a bow).
There exist a few quest items which can be harvested in some maps (particularly grade 1 areas), although they are not materials. It is believed they were items from past or future seasonal events, but were somehow patched in the game.
Contrary to grade 5 materials harvested on East Sea Plain, materials found in Dragon's Den and Mount Babel (e.g. Rabbit Skin, Pear Lumber) have an extremely low success rate of being obtained. This is not a glitch, but rather a known nerf for these collection areas. You may use a Little Forager Fairy or Forager Fairy to harvest them.
In order to raise your collection skill, it is required to change job to Commoner. It is recommended to only level one profession and create a new character to collect another type of materials, unless you want to level your Commoner. Using Commoner's Springs can also give more skill points to raise them.
- ame's Material Collection Guide by Tsubame [archived page]
- Collection Grounds Locations by Sakura301