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USGS Spectral Library Version 7 Sample Description

Kokaly, R.F., Clark, R.N., Swayze, G.A., Livo, K.E., Hoefen, T.M., Pearson, N.C., Wise, R.A., Benzel, W.M., Lowers, H.A., Driscoll, R.L., and Klein, A.J., 2017, USGS Spectral Library Version 7: U.S. Geological Survey Data Series 1035, 61 p., https://doi.org/10.3133/ds1035
For more information on the library, see: local link web link

TITLE: Glauconite HS313 DESCRIPT

DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: HS313.1B, HS313.3B, HS313.4B, HS313.6

MINERAL_TYPE: Phyllosilicate

MINERAL: Glauconite (Mica group)

FORMULA: (K,Na)(Fe+3,Al,Mg)2(Si,Al)4O10(OH)2

FORMULA_HTML: (K,Na)(Fe+3,Al,Mg)2(Si,Al)4O10(OH)2

COLLECTION_LOCALITY: South Dakota

ORIGINAL_DONOR: Hunt and Salisbury Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Grain size fractions are indicated by the extension after the sample number:
.1B = <5 µm
.3B = 74-250 µm
.4B = 250-1200 µm
.6 = cut slab

IMAGE_OF_SAMPLE:
Photo of sample

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

Quartz - major component
1M mica (phlogopite, glauconite) - major component

Konnert, Judith and Marta Flohr, 1992, unpublished data, USGS Reston, VA.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: None # XRF, EPMA, ICP(Trace), WChem

COMPOSITION_TRACE: None

COMPOSITION_DISCUSSION:

No analysis.

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

Optical examination gives the following mineral mode:

70 vol% glauconite
population 1: average grain size= 230µm 65 vol%
population 2: average grain size= 8µm 5 vol%

30 vol% quartz and feldspar grains
population 3: average grain size= 260µm 30 vol%

average grain size populations = 234µm

Large rounded glauconite grains whose surfaces are 60% covered with smaller glauconite. Some of the quartz and feldspar grains are Fe-stained and partially glauconite coated. Glauconite grains have slight yellow-green pleochroism. G. Swayze

END_MICROSCOPIC_EXAMINATION.

SPECTROSCOPIC_DISCUSSION:

END_SPECTROSCOPIC_DISCUSSION.

SPECTRAL_PURITY: 1c2_3_4_ # Glauconite HS313.1B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1c2c3c4c # Glauconite HS313.3B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1c2_3_4_ # Glauconite HS313.4B # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns
SPECTRAL_PURITY: 1c2_3_4_ # Glauconite HS313.6 # 1= 0.2-3, 2= 1.5-6, 3= 6-25, 4= 20-150 microns