4,000 B.C. African Hybrid CraftsPeople Discovered Heating Metal Rock Turn Liquid

THE END OF THE NEOLITHIC  AGE

Between 4000 and 3000  B.C., New developments began to affect Neolithic towns in some areas, The use of metals marked a new level of human (what kind of human?) control over the environment and its resources. (If Black people have no concern for civilized Prehistory and history, they have lost covilized experience--for what people the world history speaks of here? It must be known or the sense of human civilization is retarded.) More:

Even before 4000 B.C., the civilized Hybrid craftspeople had discovered that by heating metal-bearing rock, they could turn the metal to liquid. (Where were the Indo-European at this time? Answer: They had no civilized occupation but to, pass time at the Asian Steppe.)    The liquid metal could then be cast in molds to make tools and weapons. 

Copper was the first metal to be used in making tools. After 4000 B.C., craftsoeople in western Asia discovered that a combination of copper and tin created bronze, a metal far harder and more durable than copper.  So at the era we see that copper and Tin; made Bronze...it interm phased out the uncivilized homo erectus white people Stone Tools . Take notice of the time in history.