these complex societies, Sumer and Egypt, arose in places that served as trade
corridors. Sumer, in southern Mesopotamia, had the metal-rich Anatolian
highlands to the north and the Persian Gulf, leading into the Indian Ocean,
to the south. In Egypt, the Nile Valley provided the only direct access
between the Mediterranean basin and the interior of Africa. It was here in
hot lands with lots of river water and an abundance of grain that trade would
begin to spread its tentacles from interregional to intercontinental systems.
A closer look: obsidian and amber
Two non-perishable commodities that serve as good examples of how long-
distance trade worked in the Neolithic and Bronze Ages are obsidian and
amber. Obsidian is volcanic glass formed by the cooling of viscid lava. It is
black with a bright luster, spherulitic, hard but brittle, easilyflaked, and
almost indestructible. Amber is a yellow to brown translucent fossil resin
that comes in different varieties depending on transparency and compactness.
Compared to stone or metal, it is a soft, light material that is easily cut and
takes afine polish.
In the prehistoric world, nothing made a sharper edge for knives, daggers,
scrapers, razors, sickles, and projectile points for spears, harpoons, and
arrowheads than obsidian. It was utilitarian but not essential: other materials
such asflint and chert were acceptable substitutes, and modern observers
have sometimes referred to obsidian as“rich man’sflint.”It was the rock of
choice for cutting as well as a status symbol. By Neolithic standards, it was a
high-value item. Obsidian can be found only where there has been recent
volcanic activity. Areas between deposits are completely devoid of it.
Outcroppings are usually small and homogeneous in composition, and var-
iations in trace elements make each source chemically distinct. As a result,
testing can easily determine where a particular piece came from. This makes
it a good indicator of trade routes, and indeed obsidian represents the earliest
example of the widespread distribution of a non-perishable product.
According to the Roman naturalist Pliny, obsidian was named for a fellow
countryman, one Obsius, who discovered it in Ethiopia. Early man in Africa
did use hand axes of obsidian although this was 100,000 years before Obsius
lived. And Obsius did not have to go all the way to Ethiopia tofind it since
the Natufians, a proto-Neolithic culture of Southwest Asia, started trading
for obsidian 10,000 years earlier. Obsidian may not have been the earliest
commodity exchanged on a large scale across long distances, but it is the
earliest for which substantial archaeological evidence remains.
Despite the advantage we enjoy in being able to determine the sources of
obsidian, its trade was complex, and the various nuances involved are still
not completely understood. We are not even sure whether it was ever traded
on a for-profit basis by professional merchants. In certain instances, it was
definitely not, but in others there is just enough circumstantial evidence to
In the beginning 19