Hagendorfite
Encyclopedia
Hagendorfite is an iron
phosphate mineral
with the chemical formula of (Na,Ca)MnFe2(PO4)3 and is named after where the mineral was discovered, Hagendorf-Süd, Bavaria
, Germany
.
Hagendorfite is in the monoclinic crystal class; the mineral's internal symmetry consists of three axes with unequal length. Furthermore, the angles between two of the axes is 90° while the other angle is less than 90°. Monoclinic minerals contain a twofold rotation axis where they can be rotated 360° and have the crystal face repeat every 180°. They also have the characteristic mirror plane, which can produce a perfect mirror image when divided in two.
Hagendorfite belongs to the monoclinic crystal class, so it is assigned to the biaxial optical class. Hagendorfite's optic sign, which is negative, is proven by examining its interference figure. Biaxial minerals, including Hagendorfite, have three indices of refraction which may or may not correspond with the mineral's unequally lengthened axes. A refractive index will provide the ratio of the speed of light in a vacuum with the speed of light in the mineral. A single refractive index is given when two rays of light vibrate in the mineral's circular section and move along the optic axes.
course-grained rocks called pegmatites or in the phosphatic nodules in shale
. Although hagendorfite was first discovered in Bavaria, Germany, it has since been found in the Southern Province in Rwanda
, the Sowie Mountains in Poland
, and New Hampshire
in the USA. Hagendorfite is of interest to mineralogists researching phosphate-bearing pegmatites or the dickinsonite series. Hagendorfite is associated with the dickinsonite series and with other mineral members including varulite, alluarrdite, and manganalluaudite.
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...
phosphate mineral
Phosphate minerals
Phosphate minerals are those minerals that contain the tetrahedrally coordinated phosphate anion along with the freely substituting arsenate and vanadate...
with the chemical formula of (Na,Ca)MnFe2(PO4)3 and is named after where the mineral was discovered, Hagendorf-Süd, Bavaria
Bavaria
Bavaria, formally the Free State of Bavaria is a state of Germany, located in the southeast of Germany. With an area of , it is the largest state by area, forming almost 20% of the total land area of Germany...
, Germany
Germany
Germany , officially the Federal Republic of Germany , is a federal parliamentary republic in Europe. The country consists of 16 states while the capital and largest city is Berlin. Germany covers an area of 357,021 km2 and has a largely temperate seasonal climate...
.
Hagendorfite is in the monoclinic crystal class; the mineral's internal symmetry consists of three axes with unequal length. Furthermore, the angles between two of the axes is 90° while the other angle is less than 90°. Monoclinic minerals contain a twofold rotation axis where they can be rotated 360° and have the crystal face repeat every 180°. They also have the characteristic mirror plane, which can produce a perfect mirror image when divided in two.
Hagendorfite belongs to the monoclinic crystal class, so it is assigned to the biaxial optical class. Hagendorfite's optic sign, which is negative, is proven by examining its interference figure. Biaxial minerals, including Hagendorfite, have three indices of refraction which may or may not correspond with the mineral's unequally lengthened axes. A refractive index will provide the ratio of the speed of light in a vacuum with the speed of light in the mineral. A single refractive index is given when two rays of light vibrate in the mineral's circular section and move along the optic axes.
Occurrence
The mineral is found in various locations around the world. Hagendorfite occurs in complex graniteGranite
Granite is a common and widely occurring type of intrusive, felsic, igneous rock. Granite usually has a medium- to coarse-grained texture. Occasionally some individual crystals are larger than the groundmass, in which case the texture is known as porphyritic. A granitic rock with a porphyritic...
course-grained rocks called pegmatites or in the phosphatic nodules in shale
Shale
Shale is a fine-grained, clastic sedimentary rock composed of mud that is a mix of flakes of clay minerals and tiny fragments of other minerals, especially quartz and calcite. The ratio of clay to other minerals is variable. Shale is characterized by breaks along thin laminae or parallel layering...
. Although hagendorfite was first discovered in Bavaria, Germany, it has since been found in the Southern Province in Rwanda
Rwanda
Rwanda or , officially the Republic of Rwanda , is a country in central and eastern Africa with a population of approximately 11.4 million . Rwanda is located a few degrees south of the Equator, and is bordered by Uganda, Tanzania, Burundi and the Democratic Republic of the Congo...
, the Sowie Mountains in Poland
Poland
Poland , officially the Republic of Poland , is a country in Central Europe bordered by Germany to the west; the Czech Republic and Slovakia to the south; Ukraine, Belarus and Lithuania to the east; and the Baltic Sea and Kaliningrad Oblast, a Russian exclave, to the north...
, and New Hampshire
New Hampshire
New Hampshire is a state in the New England region of the northeastern United States of America. The state was named after the southern English county of Hampshire. It is bordered by Massachusetts to the south, Vermont to the west, Maine and the Atlantic Ocean to the east, and the Canadian...
in the USA. Hagendorfite is of interest to mineralogists researching phosphate-bearing pegmatites or the dickinsonite series. Hagendorfite is associated with the dickinsonite series and with other mineral members including varulite, alluarrdite, and manganalluaudite.