Complex sentence: The valley was the source of lapis for the ancient Egyptian and Mesopotamian civilizations, as well as the later Greek and Roman; during the height of the Indus valley civilization about 2000 B.C., the Harappan colony now known as Shortugai was established near the lapis mines.
Split into simpler sentences: The valley was the source of lapis for the ancient Egyptian and Mesopotamian civilizations, as well as the later Greek and Roman. During the height of the Indus valley civilization about 2000 B.C., the Harappan colony now known as Shortugai was established near the lapis mines.