Annoying Riddle:

The riddle is like this: there is a list of items and a list of hints. Apparently, all the items have one thing in common but I have yet to figure it out. Please help!

Here is the list of items:
Brachiosaurus
Knife
Almond
Coal
Moon
Helicopter
Frag
Unicorn
Tiber
Pasta
Basilisk
Scales
Snakes
America
Rhubarb
Tacos

Here is the list of hints given:
1. They are not all nouns *
2. They do not all have vowels *
3. They are not all on the list *
4. They are not related to the thing above or below them
5. They have ONE thing in common
6. A frag is a Fragmentation grenade.
7.Tiber is a river.
8. They are not all capitalized *
9. They are not carbon based, nope. *

**The ones with * are all answers given previously but are wrong.