'Black' in the Bible

And do not swear by your head, because you are not able to make one hair white or black.

And when he opened the third seal, I heard the third living creature saying, "Come!" And I looked, and behold, a black horse, and the one seated on it had a balance scale in his hand.

And I watched when he opened the sixth seal, and a great earthquake took place, and the sun became black like sackcloth made of hair, and the whole moon became like blood,