The moon is made of rocks which includes silica, alumina, magnesia and sodium oxide. In addition, it has a core that has a radius of 240 kilometers which is rich in iron. Other constituents of the moon include nickel and sulfur that is alloyed with metallic iron.
Theory is the earth and another planet collided billions of years ago, scientists named this planet Thea. Earth survived and Thea was destroyed, debris was thrown into orbit around earth, this debris eventually came together and formed the moon. So the moon is made of earth and Thea. and all their combined elements