Augite

<h2 id="characteristics">Characteristics</h2>

<p>Augite is a <a href="/facts/Solid_solution/Mla7z8dc">solid solution</a> in the <a href="/facts/Pyroxene/hWMTLF9o">pyroxene</a> group. <a href="/facts/Diopside/vyRkJB2W">Diopside</a> and <a href="/facts/Hedenbergite/rLoyjbnu">hedenbergite</a> are important endmembers in augite, but augite can also contain significant <a href="/facts/Aluminium/7wmR8jYE">aluminium</a>, <a href="/facts/Titanium/53ArnDoy">titanium</a>, and <a href="/facts/Sodium/eYuSPu2V">sodium</a> and other elements. The calcium content of augite is limited by a <a href="/facts/Miscibility_gap/m24xwIes">miscibility gap</a> between it and <a href="/facts/Pigeonite/LR6IKpvY">pigeonite</a> and <a href="/facts/Orthopyroxene/hWMTLF9o">orthopyroxene</a>: when occurring with either of these other pyroxenes, the calcium content of augite is a function of temperature and pressure, but mostly of temperature, and so can be useful in reconstructing temperature histories of rocks. With declining temperature, augite may exsolve lamellae of pigeonite and/or orthopyroxene. There is also a miscibility gap between augite and <a href="/facts/Omphacite/UUTvwsM7">omphacite</a>, but this gap occurs at higher temperatures. There are no industrial or economic uses for this mineral.<a class="footnote-ref" id="fnref:1" href="#fn:1"><sup>1</sup></a><a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a>
</p>
<h2 id="locations">Locations</h2>
<p>Augite is an essential mineral in <a href="/facts/Mafic/mVL7Ahuw">mafic</a> <a href="/facts/Igneous_rock/xeMJhUah">igneous rocks</a>; for example, <a href="/facts/Gabbro/79gTqpyg">gabbro</a> and <a href="/facts/Basalt/uhbwGPTb">basalt</a> and common in <a href="/facts/Ultramafic/7qAapP1d">ultramafic</a> rocks. It also occurs in relatively high-temperature <a href="/facts/Metamorphic_rock/JRp6dsCm">metamorphic rocks</a> such as mafic <a href="/facts/Granulite/5vxpnm3U">granulite</a> and metamorphosed iron formations. It commonly occurs in association with <a href="/facts/Orthoclase/xTjjm0gP">orthoclase</a>, <a href="/facts/Sanidine/V7smg9oq">sanidine</a>, <a href="/facts/Labradorite/PyDfR62q">labradorite</a>, <a href="/facts/Olivine/tLLL4rae">olivine</a>, <a href="/facts/Leucite/l1uVJHtm">leucite</a>, <a href="/facts/Amphibole/2Nf6RDRA">amphiboles</a> and other pyroxenes.<a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a>
</p><p>Occasional specimens have a shiny appearance that give rise to the mineral's name, which is from the Greek <i>augites</i>, meaning "brightness", although ordinary specimens have a dull (dark green, brown or black) luster. It was named by <a href="/facts/Abraham_Gottlob_Werner/WH8b5tqu">Abraham Gottlob Werner</a> in 1792.<a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a>
</p>
<h2 id="see-also">See also</h2>
<ul><li><a href="/facts/Fassaite/Fat8abNn">Fassaite</a></li></ul>

<h2 id="further-reading">Further reading</h2>

Wikimedia Commons has media related to Augite.

<ul><li>Deer, W. A., Howie, R. A., and Zussman, J. (1992). <i><a href="/facts/An_introduction_to_the_rock-forming_minerals/dmQ8vwzy">An introduction to the rock-forming minerals</a> (2nd ed.)</i>. Harlow: Longman <a href="/facts/ISBN_(identifier)/15AdSPa9">ISBN</a> 0-582-30094-0</li></ul>

<h2 id="references">References</h2>

<ol>
<li id="fn:1"><p>Klein, Cornelius; Hurlbut, Cornelius S. Jr. (1993). Manual of mineralogy : (after James D. Dana) (21st ed.). New York: Wiley. pp. 481–482. ISBN 047157452X. <a href="047157452X" target="_blank">047157452X</a> <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li>
<li id="fn:2"><p>Nesse, William D. (2000). Introduction to mineralogy. New York: Oxford University Press. pp. 268–269. ISBN 9780195106916. <a href="9780195106916" target="_blank">9780195106916</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li>
<li id="fn:3"><p>Handbook of Mineralogy <a href="http://rruff.geo.arizona.edu/doclib/hom/augite.pdf" target="_blank">http://rruff.geo.arizona.edu/doclib/hom/augite.pdf</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li>
<li id="fn:4"><p>Augite on Mindat.org <a href="http://www.mindat.org/min-419.html" target="_blank">http://www.mindat.org/min-419.html</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li>
</ol>

Augite open-in-new

Augite