This specimen is an example of an unusual mineral that formed in a simple pegmatite environment.
Simple Pegmatites: Unusual Minerals
Some of the less commonly formed minerals associated with simple pegmatites include fluorite, rose quartz, scheelite, and chrysoberyl. Of interest are a group of minerals that contain the rare earth metals, or those elements with atomic number 57–71 (lanthanum to lutetium). Additionally, minerals containing such equally uncommon elements as yttrium, beryllium, scandium, zirconium, hafnium, and thorium also may be present. These elements have gained great importance in space-age technology because they are used, among many other ways, to produce metal alloys with specialized properties — for example, the ability to withstand very high temperatures.
Llano Co., Texas