Misc: In transport, what do the letters HGV stand for?

Questions

Neture What do oak trees grow from?

Not Telling ;-) What would be kept in an "aviary"?

Not Telling ;-) Where is the Ocean of Storms located?

Not Telling ;-) Who is Robert Zimmermann?

Not telling ;-P What are these: chrysolite, beryl, jasper, and tourmaline?