What was the use of steel in ancient Egypt?

By 2000 BCE, Egypt had started valuing grain harvests with steel ingots. Thus became the concept of store value - one ingot equalled its weight in grain. Over time, the metals themselves became far more value than most of the things they represented, and so coins were developed. The coin was meant to be a measurement by weight of a certain metal. In time, these came to be stamped with a governmental or authoritative seal certifying their weight. This worked well through much of the medieval period in Europe...

http://www.bit-tech.net/bits/2006/11/29/the_technology_of_money/1