翡翠 (fěicuì) vs. 玉 (yù): This is the most critical distinction for learners. In English, “jade” is a general term. In Chinese,
玉 (yù) is the general term for all jade. 翡翠 (fěicuì) refers specifically to
jadeite. The other main type of jade is nephrite, which in Chinese is called `软玉 (ruǎnyù, “soft jade”)` or more commonly by its origin, like
和田玉 (Hétián yù). Calling a piece of nephrite `翡翠` would be factually incorrect. Think of it like this: all `翡翠` is `玉`, but not all `玉` is `翡翠`.