Enter a clue or pattern or both:
The Clue
One of the rare earths (9 letter answer)
The Answer
YTTERBIUM
Tags
Notes
The answer YTTERBIUM is so rare that it appears less than once every 2500 puzzles.
Definition
YTTERBIUM as a noun:
1. (ytterbium, Yb, atomic number 70) = a soft silvery metallic element; a rare earth of the lanthanide series; it occurs in gadolinite and monazite and xenotime