Answer:
Glittering points that downward thrust. Sparkling spears that never rust.
I grow where no flower grows, where no light touches the walls, up or down, that I don't care, was here before people were.
Gets rid of bad ones, short and tall. Tightens when used, one size fits all.
Long and think, red within, with a nail at the end.
Has no feet, but travels far. Is literate, but not a scholar. Has no mouth, yet clearly speaks.
What is so fragile that saying its name breaks it?
Difficult
Animal
Easy
Food
Funny
Kids
Logic
What am I?