Answer:
I go up and never come down no matter how hard you wish. As I get higher more wrinkles crawl onto your face.
Of the king I am blue and of the peasant I am red. Of the frog I am cold and of the dog I am hot instead.
You write on me and secrets I can keep. In places never seen. I spin like a top. Though stiff as a board I'm often described like a mop.
What do people spend a lot of money on every year, but never want to use?
I am partially baked. I am not completely lit. I am a portion of the moon. I am lesser than full wit. I am a divider of the hour. I am not a total lie. I am a sibling through one parent.
It flows out of the soil, It burns you if it boils, And holds us in its coils, More valuable than gold, As black as it is old.