Analytical tests such as physical property tests, Raman spectroscopy, and X-ray diffraction are not only helpful, but oftentimes essential for both discovering the identity of and gaining structural information about distinct minerals. In this case, these tests can be used to discover the chemical composition of a ferroaxinite-tinzenite blend. Pegmatite formation in the fourth stage of mineral evolution represents the first time minerals such as axinite formed as well as a substantial mineralization event. Research suggests that boron in the form of boric acid may play a previously unknown yet crucial role in the formation of pegmatites, and therefore axinite, and creating the necessary conditions that resulted this crystallization event.
Axinite {(Ca,Fe,Mg,Mn)3Al2BSi4O15(OH)} is a subgroup of
minerals with slightly varying composition
Ford 1903. The triclinic mineral often grows
in very flat, tabular crystals with sharp axe-like edges, giving it its name
Ford 1903. A
few variations of the same chemical formula are considered to be axinites. They
include ferroaxinite, magnesio-axinite, manganaxinite, and tinzenite
Ford 1903.
These minerals share a base formula of Ca2
XAl2BOSi4O15(OH), where
"X" can vary in composition. For example, ferroaxinite replaces
the "X" with a Fe2+ ion. On the other hand, magnesio-axinite and
manganaxinite contain magnesium and manganese ions in place of the
"X," respectively. Finally, the last variation of axinite, tinzenite,
contains both Fe2+ and Mn2+ ions, and only one calcium ion. These different compositions
result in slightly different properties for the individual minerals, such as
color. Axinites form in very obscure conditions and, as a result, are therefore relatively rare. They are nearly exclusively found across the world in granitic, near-surface pegmatites and areas of hydrothermal activity
Stability of tourmali....