Element 72 · Transition Metal
Hafnium
Hafnium is the corrosion-resistant nuclear control rod metal — and now the gate dielectric in microchips.
Element Facts
SYMBOL
Hf
ATOMIC NO.
72
ATOMIC WEIGHT
178.49
CATEGORY
Transition Metal
PERIOD
Period 6
GROUP
Group 4
Discovery & History
Hafnium was the last stable naturally occurring element to be discovered — specifically sought after Mendeleev’s periodic table predicted its existence. Found in 1923 by Dirk Coster and George de Hevesy in zirconium ores from Norway, using X-ray spectroscopy. Named after Hafnia, the Latin name for Copenhagen. Because hafnium is chemically almost identical to zirconium and always found with it, separation required extensive fractional crystallisation. Its high neutron-absorption cross-section makes pure hafnium invaluable in nuclear reactor control rods.
Quick Overview
Hafnium is element 72, chemically nearly identical to zirconium and difficult to separate from it. The two were not distinguished until 1923. Used wherever zirconium's neutron-absorbing trace impurity content matters — particularly nuclear control rods.
Where It's Used
Nuclear submarine reactor control rods. Hafnium oxide gate dielectric in advanced semiconductor manufacturing (replaced silicon dioxide in CPU transistors from 2007 onward). Plasma cutting torch electrodes. Aerospace superalloys.
Can You Sell It?
Why QuickStop Metals doesn’t buy Hafnium:
Specialist nuclear and semiconductor applications only. Hafnium scrap goes to specialist refiners. No general scrap market.
Price Guide
Hafnium metal trades at approximately £600–1,400/kg. Produced exclusively as a byproduct of nuclear-grade zirconium refining. Hafnium is a strategic material for nuclear and semiconductor industries but not traded at scrap yards.