Erbium is a chemical element in
the lanthanide series, with the symbol Er and an atomic
number of 68. It has an atomic weight of 167.259.
Things you might not know about
Erbium:
- The concentration of erbium in the Earth
crust is about 2.8 mg/kg. This concentration is enough
to make erbium about 45th in elemental abundance in the Earth's
crust, more common than more familiar elements such as lead.
- Erbium oxide has a pink color, and is
sometimes used as a colorant for glass, cubic zirconia and
porcelain. The glass is then often used in sunglasses and cheap
jewelry.
- Used in nuclear technology in
neutron-absorbing control rods.
See GC2XAY2 - Hydrogen, for an explanation
about this series of caches.