Thulium

69
Tm
168.93421

thulium.gif (6643 bytes)
Thulium is used in lasers.

Properties

Symbol Name Atomic Number Atomic Weight Group Number
Tm Thulium 69 168.93421

Description

Standard State: solid at 298 K
Color: Silvery white

Discovered in 1879 by Cleve.  Thulium occurs in small quantities along with other rare earth's in a number of minerals. IT is obtained commercially form monazite, which contains about .007% of the element.  Thulium is the least abundant of the earth elements, but with new sources recently discovered, it is now considered to be about as rare as silver, gold, or cadmium.  Ion-exchange and solvent extraction techniques have recently permitted much easier separation of the rare earth's, with much lower costs. Because of the high cost of Thulium there has hardly been any practical applications for the element.  Natural thulium also has possible use in ferrites used in microwave equipment.