What Am I Riddles

Question: I'm teary-eyed but never cry.
Silver-tongued, but never lie.
Double-winged, but never fly.
Air-cooled, but never dry.

What am I?

Question: In a marble hall as white as milk, Lined with skin as soft as silk, Within a fountain crystal clear, A golden orb does appear, There are no doors to this stronghold, Yet thieves break in and steal the gold. What am I?

Question: Looking at my face, I'm no more than six.
Look at the rest of me and I'm 21.
You'll see my twin and me in Las Vegas.
Say my name and you'd be uttering a threat.

What am I?

Question: When is... 5>0, 0>2 and 2>5? Hint: Hands

Question: What is red and white at home, but can never be that when it leaves?