U.S. Geological Survey home page

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: Hematite.02+Quartz.98 GDS76 DESCRIPT

DOCUMENTATION_FORMAT: MIXTURE

SAMPLE_ID: GDS76

MIXTURE_TYPE: Intimate

MIXTURE: Hematite (2%) + Quartz (98%) (Hematite group)

FORMULA: alpha-Fe2O3 + SiO2

FORMULA_HTML: alpha-Fe2O3 + SiO2

COLLECTION_LOCALITY: Laboratory mixture

ORIGINAL_DONOR: Unknown

CURRENT_SAMPLE_LOCATION: USGS Spectroscopy sample collection library - Denver, Colorado

ULTIMATE_SAMPLE_LOCATION: USGS Spectroscopy sample collection library - Denver, Colorado

SAMPLE_DESCRIPTION:

Hematite GDS27 2 wt% + 98 wt% Pure crystal quartz (less than 250 µm grain sizes)

END_SAMPLE_DESCRIPTION.

XRD_ANALYSIS:

40 kV - 30 mA, 6.5-9.5 keV
File: hemqtz76_mdi (smear on quartz plate)
References: Huebner's reference patterns; Borg and Smith (1969); PDF2 #33-1161, 33-664
Found: Quartz, trace hematite

Comments: Quartz reflections are extremely sharp with excellent resolution of alpha1-alpha2 components. Six very weak to barely significant hematite reflections were observed. The strip chart shows reflections at 3.11, 3.07, 3.06, and 2.66 angstroms; only the 2.66 angstrom peak appears significant in the raw data, and none are present after routine filtering by Jade. There are several other very weak reflections (3.11-3.06, 2.66 angstroms) seen only in the strip chart.

END_XRD_ANALYSIS.

COMPOSITIONAL_ANALYSIS_TYPE: NONE

COMPOSITION_TRACE:

COMPOSITION_DISCUSSION:

END_COMPOSITION_DISCUSSION.

MICROSCOPIC_EXAMINATION:

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