Holmium Element Number 67 Ho  

 Holmium is a shiny silver rare earth metal with decent stability in dry air. Holmium has a very pretty structure with and interesting fibrous look. Holmium like most rare earth metals is found in monazite sand, at a ratio of approx. 0.05% about the same as Europium.

Holmium has few applications, one being a glass additive for yellow. Holmium Oxide is added to artificial diamonds as well. because Holmium Oxide has a certain spectral range the material can be used as and optical spectrometer standard.

Holmium holds the title of highest magnetic strength of any element, and therefore can be used as a magnetic flux concentrator In normal terms, that simply means a piece of Holmium can be placed on the magnetic pole to extend or amplify the field. In the case of Holmium it is generally used in electromagnet applications. A good example of a device with a magnet and pole piece is a loud speaker.

This element is also a great neutron absorber, and used as a control rod material in nuclear power applications. Holmium is also used in photon spectrometers as a calibration standard.  I have 2 samples of Holmium and one is quite boring while the other is very exciting, with such a beautiful structure.

These 2 pieces of pure Holmium show both dendritic,  and cast material.

Ho  67  Lanthanide  AW:164.93032  D:8.79  MP:2662  BP:4928 

Erbium Element Number 68 Er 

Here is a small piece of pure Erbium metal with a rough surface that displays the metal nicely.

Er  68  Lanthanide  AW:167.259  D:9.06  MP:2784  BP:5194

Erbium is yet another Lanthanide metal found in gadolinite. The element is not found in native state on earth. Erbium has a higher abundance than most rare earths, and lands around 45th in the crust. like many rare earth metals Erbium Oxide is used in glass and ceramic colorants, as a pretty pink. 

Erbium is a good neutron absorber, and used in the nuclear industry. Erbium has uses in fiber optics as a dopant. Erbium lasers can be used in medical and dental fields as Erbium YAG lasers which can cut at shallow depths. Another use in lasers is a Erbium-Ytterbium doped fiber optic laser used in welding and cutting. These Er-Yb lases are very powerful and comparable to Co2 laser tubes in power.

Erbium can be used in special alloys with Nickle that can withstand extreme cold. Erbium can also alloyed with Vanadium to improve workability. I am considering someday upgrading my sample to a larger dendritic form.