Thulium - Periodic Table of Videos
The team at periodicvideos has created a TED-Ed Lesson for every element of the periodic table. Thulium, element number 69, is a hard one to isolate and thus, very expensive. However, there is promise for an increased use of this element.
Have you ever done a recrystallization in your school lab? And/ or a crystallization? What did you get crystals of?