I am both worn by a tree, and a symbol of royalty. Even a coin can describe me. What am I?

brown and smooth, meant to soothe, though I prefer it a little more rocky. used many a way, from sauces to saute, I make things divine. alone I am fine, paired with a figurative log and ants, I am the missing piece.

Its bells don't ring; they shine red, green, and yellow Tiny black seeds that season your meal, Or thin, red, or green when you need some heat

You thought it was songs, But the app said no? 'Radio Art' ? It's what helps the heat flow...

From regal crowns, I proudly sprout, In forest halls, where creatures rout. A branching peak on nature's throne, Majestic horns of bone alone.