What materials have been used to make mosaics throughout history?

Well, older mosaics often were made of pieces of glass or small rough pieces of stone. Floor mosaics were made out of stone. A glue like paste was used to stick the pieces onto the walls. Michaelangelo's mosaics were often made out of colored tile and naturally colored stones. He also used glass.

Photojournalism adds emphasis and power. if some one told you that a bomb blew up the world trade center, you wouldn’t have believed them until you saw it on the tv or in the newspaper.