DOCUMENTATION_FORMAT: MINERAL

SAMPLE_ID: HS313

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 Salibury Collection

CURRENT_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

ULTIMATE_SAMPLE_LOCATION: USGS Denver Spectroscopy Laboratory

SAMPLE_DESCRIPTION:

Sample measured was HS313.3B which was dry sieved to the grain size interval 74-250 µm.

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Konnert, Judith and Marta Flohr, 1992, unpublished data, USGS Reston, VA.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, EM(WDS), 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
pop 1 av gr sz = 230µm 65 vol%
pop 2 av gr sz = 8µm 5 vol%

30 vol% quartz and feldspar grains
pop 3 av gr sz = 260µm 30 vol%

av gr sz 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: 1_2_3_4_

LIB_SPECTRA_HED: where Wave Range Av_Rs_Pwr Comment

LIB_SPECTRA: splib04a r 1760 0.2-3.0µm 200 g.s.= 234 µm

LIB_SPECTRA: splib05a r ____ 0.2-3.0µm 200 g.s.=

LIB_SPECTRA: splib06a r ____ 1.5-25µm 250 g.s.=