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Spectra Used in Figures

Metadata Updated: January 19, 2026

This dataset contains reflectance and transmission spectra of unexpanded and expanded vermiculite ore, and handpicked flakes of phlogopite, hydrobiotite, and vermiculite. These samples were collected from mines near Enoree, South Carolina; Libby, Montana; Louisa, Virginia; Palabora, Llano, Texas; and South Africa. Spectra are identified as either reflectance or transmission in the alphanumeric file names and correlate to specpr record numbers designated in the manuscript figures in which they are shown. These transmission spectra were converted to absorbance in many of the figures. Spectra of talc, fibrous richterite amphibole, and serpentine are from well characterized samples from Feiser Mine, Ruby Mountains, Montana; Libby, Montana; and a NIOSH chrysotile standard (CH29) respectively. The talc sample is described in the U.S. Geological Survey Spectral Library (Kokaly and others, 2017). Some vermiculite samples were K-exchanged to facilitate spectral comparisons.

Access & Use Information

Public: This dataset is intended for public access and use. License: No license information was provided. If this work was prepared by an officer or employee of the United States government as part of that person's official duties it is considered a U.S. Government Work.

Downloads & Resources

Dates

Metadata Created Date January 11, 2026
Metadata Updated Date January 19, 2026

Metadata Source

Harvested from DOI USGS DCAT-US

Additional Metadata

Resource Type Dataset
Metadata Created Date January 11, 2026
Metadata Updated Date January 19, 2026
Publisher U.S. Geological Survey
Maintainer
Identifier http://datainventory.doi.gov/id/dataset/USGS_58797a45e4b0847d353f4044
Data Last Modified 2020-09-29T00:00:00Z
Category geospatial
Public Access Level public
Bureau Code 010:12
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Metadata Catalog ID https://ddi.doi.gov/usgs-data.json
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Datagov Dedupe Retained 20260119153509
Harvest Object Id ae9c7d44-1d70-4bda-a367-a984746ddf6b
Harvest Source Id 2b80d118-ab3a-48ba-bd93-996bbacefac2
Harvest Source Title DOI USGS DCAT-US
Metadata Type geospatial
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Source Datajson Identifier True
Source Hash 9ba51e6cd48aaaebdda31919f0249f978dddfc96fb14d44164e4db02e2ee3cc6
Source Schema Version 1.1
Spatial {"type": "Polygon", "coordinates": -128.7597656235, 23.684373489276, -128.7597656235, 49.922653763102, -62.490234376141, 49.922653763102, -62.490234376141, 23.684373489276, -128.7597656235, 23.684373489276}

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