Gerzeh bead
Date: no date
Material: Meteorite
Provenance: 5-300 year old tomb Gerzah cemetary, Egypt
Iron Beads
The iron beads come from a tomb in the prehistoric Gerzeh cemetery, on the bank of the Nile about 70 kilometers south of Cairo. The tomb belonged to a “fair-sized boy,” according to notes the excavator took when the tomb was discovered more than a century ago. Seven iron beads were placed around the boy’s neck and waist. The beads appear to be jewelry, and were found with other materials like obsidian and ivory.
Diane Johnson, a geochemist at the Open University in England, and her colleagues analyzed the chemical composition of one of the iron beads from the tomb to settle a century-long debate about the origin of the metal: terrestrial or celestial.
The ancient bead looks very different today than it did millennia ago: It is rusted, and the surface of the bead is covered with sand from the tomb. But in some areas, the rust has fallen off, allowing researchers to look inside and analyze the original metal using a scanning electron microscope. They found that the iron consists of an alloy with approximately 30 percent nickel — which is a signature of iron meteorites. When metallic iron coalesces {Grow together/into one body) to form the core of an asteroid or planet, it takes most of the nickel with it, same with the Earth. Most iron ore mined on Earth’s surface has very little nickel, but iron with a lot of nickel can be found on the surface in the parts of broken-up cores of ancient asteroids, which fall to Earth as meteorites.
Date: no date
Material: Meteorite
Provenance: 5-300 year old tomb Gerzah cemetary, Egypt
Iron Beads
The iron beads come from a tomb in the prehistoric Gerzeh cemetery, on the bank of the Nile about 70 kilometers south of Cairo. The tomb belonged to a “fair-sized boy,” according to notes the excavator took when the tomb was discovered more than a century ago. Seven iron beads were placed around the boy’s neck and waist. The beads appear to be jewelry, and were found with other materials like obsidian and ivory.
Diane Johnson, a geochemist at the Open University in England, and her colleagues analyzed the chemical composition of one of the iron beads from the tomb to settle a century-long debate about the origin of the metal: terrestrial or celestial.
The ancient bead looks very different today than it did millennia ago: It is rusted, and the surface of the bead is covered with sand from the tomb. But in some areas, the rust has fallen off, allowing researchers to look inside and analyze the original metal using a scanning electron microscope. They found that the iron consists of an alloy with approximately 30 percent nickel — which is a signature of iron meteorites. When metallic iron coalesces {Grow together/into one body) to form the core of an asteroid or planet, it takes most of the nickel with it, same with the Earth. Most iron ore mined on Earth’s surface has very little nickel, but iron with a lot of nickel can be found on the surface in the parts of broken-up cores of ancient asteroids, which fall to Earth as meteorites.