Bible Verses About Altars: To be made of earth, or unhewn stone

An altar of earth thou shalt make unto me, and shalt sacrifice thereon thy burnt-offerings, and thy peace-offerings, thy sheep, and thine oxen: in every place where I record my name I will come unto thee and I will bless thee.

And if thou make me an altar of stone, thou shalt not build it of hewn stones; for if thou lift up thy tool upon it, thou hast polluted it.

And there shalt thou build an altar unto Jehovah thy God, an altar of stones: thou shalt lift up no iron tool upon them.

Thou shalt build the altar of Jehovah thy God of unhewn stones; and thou shalt offer burnt-offerings thereon unto Jehovah thy God: