| However, erbium is more abundant than bromine, iodine, mercury, and cadmium. |
| In the metallurgical industry, erbium is used to reduce the hardness of metals in order to improve their usefulness. |
| Most of the other rare earths are fairly transparent to thermal neutrons with cross sections ranging from 0.7 barn for cerium to 170 for erbium. |
| For the destructive lasers, meaning carbon dioxide or erbium or blends of those two, the risk of scarring is higher. |
| Yttria occurs only in a few rare minerals, and usually in company with terbium and erbium. |
| The village is Ytterby and the elements are yttrium, erbium, terbium and ytterbium. |
