@article{c31b6671ac32414a9613efb31a2c4f41,
title = "Relationships between unit-cell parameters and composition for rock-forming minerals on Earth, Mars, and other extraterrestrial bodies",
abstract = "Mathematical relationships between unit-cell parameters and chemical composition were developed for selected mineral phases observed with the CheMin X-ray diffractometer onboard the Curiosity rover in Gale crater. This study presents algorithms for estimating the chemical composition of phases based solely on X-ray diffraction data. The mineral systems include plagioclase, alkali feldspar, Mg-Fe-Ca C2/c clinopyroxene, Mg-Fe-Ca P21/c clinopyroxene, Mg-Fe-Ca orthopyroxene, Mg-Fe olivine, magnetite, and other selected spinel oxides, and alunite-jarosite. These methods assume compositions of Na-Ca for plagioclase, K-Na for alkali feldspar, Mg-Fe-Ca for pyroxene, and Mg-Fe for olivine; however, some other minor elements may occur and their impact on measured unit-cell parameters is discussed. These crystal-chemical algorithms can be applied to material of any origin, whether that origin is Earth, Mars, an extraterrestrial body, or a laboratory.",
keywords = "CheMin, Gale crater, Mars, Mars Science Laboratory, Martian Rocks and Minerals, Meteorites, Orbiters, Perspectives from Rovers, X-ray diffraction, alunite, crystal chemistry, jarosite, magnetite, olivine, plagioclase, pyroxene, spinel, unit-cell parameters",
author = "Morrison, {Shaunna M.} and Downs, {Robert T.} and Blake, {David F.} and Anirudh Prabhu and Ahmed Eleish and Vaniman, {David T.} and Ming, {Douglas W.} and Rampe, {Elizabeth B.} and Hazen, {Robert M.} and Achilles, {Cherie N.} and Treiman, {Allan H.} and Yen, {Albert S.} and Morris, {Richard V.} and Bristow, {Thomas F.} and Chipera, {Steve J.} and Sarrazin, {Philippe C.} and Fendrich, {Kim V.} and Morookian, {John Michael} and Jack Farmer and DesMarais, {David J.} and Craig, {Patricia I.}",
note = "Funding Information: We acknowledge the support of the JPL engineering and Mars Science Laboratory (MSL) operations team. The study benefited from discussions with Mike Baker concerning relationships between the compositions of olivine and pyroxene and their associated unit-cell parameters. We thank the reviewers of this manuscript, Olivier Gagn{\'e} and Bradley Jolliff, for their insightful and constructive feedback. This research was supported by NASA NNX11AP82A, MSL Investigations, and by the National Science Foundation Graduate Research Fellowship under Grant No. DGE-1143953.Any opinions, findings, or recommendations expressed herein are those of the authors and do not necessarily reflect the views of the National Aeronautics and Space Administration or the National Science Foundation. Publisher Copyright: {\textcopyright} 2018 Walter de Gruyter GmbH, Berlin/Boston 2018.",
year = "2018",
month = jun,
day = "26",
doi = "10.2138/am-2018-6123",
language = "English (US)",
volume = "103",
pages = "848--856",
journal = "American Mineralogist",
issn = "0003-004X",
publisher = "Mineralogical Society of America",
number = "6",
}