Jeffersonite is a dark green
pyroxene mineral, a manganese zinc enriched variety of
augite, chemical formula , sometimes compared to
aegirine
Aegirine is a member of the clino pyroxene group of inosilicate minerals. Aegirine is the sodium endmember of the aegirine-augite series. Aegirine has the chemical formula Na Fe Si2 O6 in which the iron is present as Fe3+. In the aegirine-augit ...
. Jeffersonite is not a recognized mineral name.
It occurs in
pegmatites where it can form crystals up to long and in the
contact metamorphic
Metamorphism is the transformation of existing rock (the protolith) to rock with a different mineral composition or texture. Metamorphism takes place at temperatures in excess of , and often also at elevated pressure or in the presence of che ...
zone between
limestone
Limestone ( calcium carbonate ) is a type of carbonate sedimentary rock which is the main source of the material lime. It is composed mostly of the minerals calcite and aragonite, which are different crystal forms of . Limestone forms whe ...
and various
intrusive rocks. It is reported from the
Sterling Hill Mine
The Sterling Hill Mine, now known as the Sterling Hill Mine Tour & Museum of Fluorescence, is a former iron and zinc mine in Ogdensburg, Sussex County, New Jersey, United States. It was the last working underground mine in New Jersey when it c ...
,
Franklin, New Jersey
Franklin is a borough in Sussex County, in the U.S. state of New Jersey. As of the 2010 United States Census, the borough's population was 5,045[South Australia
South Australia (commonly abbreviated as SA) is a state in the southern central part of Australia. It covers some of the most arid parts of the country. With a total land area of , it is the fourth-largest of Australia's states and territories ...]
and
Sweden.
External links
MindatAbandoned Mines of New Jersey
Calcium minerals
Manganese(II) minerals
Iron(II) minerals
Zinc minerals
Pyroxene group
Minerals described in 1822
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