Tantalum is a chemical element with the
symbol Ta and it has an atomic number of 73. The
atomic weight is 180.94788. 
Things you might not know about
Tantalum:
- The primary mining of tantalum is in
Australia.
- The major use for tantalum, as the metal
powder, is in the production of electronic components, mainly
capacitors and some high-power resistors.
- It is also occasionally used in precious
watches e.g. from Hublot, Montblanc and Panerai.
See GC2XAY2 - Hydrogen, for an explanation
about this series of caches.