The guide is great (i can 100% confirm the locations since i've collected there).
Mineral (Grade E) - Tempest Watchout & Sirka Observatory (Morrisen),
- Ashen Battlefield (Armenes - Dhan/Dekan only), Other "Chaos" marshlands on other maps too;
Plants (Grade E) - Bergendy Brewery (Morrisen), sometimes even in Bindstone grounds.
By the way, there are some A Grade Minerals on East Bahran Island too (hidden among the E grades), but they however are still only available to Dekan/Dhan races (or endgame players that can smack patrol NPCs).