I hang from your neck, I protect you from goo. I help potters sculpt, and help chefs too. What am I?

I’m a knot with no rope, A loop without a snare. I’m worn to look proper, Or mocked as too square. Symmetry is my disguise, Two wings, one throat. I’m tied, yet I fly. What am I?

It'll be too easy if I tell you about me directly, so: Change my second letter to E, and I'll become a holey object people use to catch things. Change my second letter to O, and I become something heavy, but backwards.

When I’m dry I may disappear In many forms I reappear Beauty truffle pies and pots Stone ceramics balls and art I am wanted needed despised and hated Depending on the day and places

With pointed fangs, I sit and wait; with piercing force, I crunch out fate. I grab victims, proclaiming might, and physically join with a single bite. What am I?