Exodus 20:25
And if you will make Me an altar of stone, you shall not build it of cut stone. For if you lift up your tool upon it, you have defiled it.
Deuteronomy 27:5-6
And you shall build an altar there to Jehovah your God, an altar of stones. You shall not lift up any iron tool on them.
Joshua 8:31
as Moses the servant of Jehovah commanded the sons of Israel, as it is written in the book of the Law of Moses, an altar of whole stones over which no man has lifted any iron. And they offered on it burnt offerings to Jehovah, and sacrificed peace offerings.
Treasury of Scripture Knowledge
Summary
And if thou wilt make me an altar of stone, thou shalt not build it of hewn stone: for if thou lift up thy tool upon it, thou hast polluted it.
General references
Bible References
And
Deuteronomy 27:5
And you shall build an altar there to Jehovah your God, an altar of stones. You shall not lift up any iron tool on them.
Joshua 8:31
as Moses the servant of Jehovah commanded the sons of Israel, as it is written in the book of the Law of Moses, an altar of whole stones over which no man has lifted any iron. And they offered on it burnt offerings to Jehovah, and sacrificed peace offerings.
General references
Leviticus 16:33
And he shall make an atonement for the holy sanctuary, and he shall make an atonement for the tabernacle of the congregation, and for the altar; and he shall make an atonement for the priests and for all the people of the congregation.