Answer:
One more than a duet.
A precious gift, yet it has no end, no beginning, and nothing in the middle.
What has no hands but might knock on your door, and if it does you better open up?
The land was white the seed was black. It'll take a good scholar to riddle me that.
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.
It is something you will never see again.
Easy
Animal
Difficult
Food
Funny
Kids
Logic
What am I?