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Clark et. al. 2003 USGS Open File Report 03-395
Spectral Library splib05a Sample Description

(For further information on spectrsocopy, see: http://speclab.cr.usgs.gov)

TITLE: Butlerite GDS25 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: GDS25

MINERAL_TYPE: Sulfate

MINERAL: Butlerite

FORMULA: Fe+3(SO4)(OH)*2H2O

FORMULA_HTML: Fe+3(SO4)(OH)•2H2O

COLLECTION_LOCALITY: MIT Collection

ORIGINAL_DONOR: Harvard Dana Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

This sample was originally called Fibroferrite (Dave Sherman). Fibroferrite and butlerite have almost the same composition, differing only in the H2O content.

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Pure butlerite.

Konnert, Judith and Marta Flohr, 1992, unpublished data, USGS Reston, VA.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EM(WDS), ICP(Trace), WChem

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

None

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

Avg. gr sz = 10 µm

Very pure sample, all fibrous grains, length fast, nearly straight extinction. Fibrous nature prevents further determination of optical properties. Since I have no optical data on this mineral type to test its identity I cannot be optically sure this is Fibroferrite. G. Swayze.

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1a2_3_4_ # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns

LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment
LIB_SPECTRA: splib04a r 765 0.2-3.0µm 200 g.s.= 10 µm
LIB_SPECTRA: splib05a r 1439 0.2-3.0µm 200 g.s.=


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