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USGS COALQUAL · Data sources · STRATA

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usgs_coalqualcommodityOfficial surveyAuthoritative

USGS COALQUAL

USGS

~7,657 U.S. coal samples, trace-element geochemistry, critical elements (REE/Y

Source

How it's published

Feed (what to expect)

Static 2015 portal scrape (no bulk endpoint); vendored CSV, re-scrape to refresh.

Cadence: static (2015)
Access: vendor-cached portal scrape; no bulk download endpoint
Format: CSV (wide: sample rows × element columns with qualifiers)
Licence: public domain
Vintage: 2015
Upstream: https://ncrdspublic.er.usgs.gov/coalqual/

Quirks

Portal-scraped via scripts/acquire_coalqual.py; archived at
Paired value + qualifier columns (e.g., Ce + Ce Q); ash-basis flag preserved in

Coal/coal-ash recognized host for critical elements; complements NGDB

Reconciliation

Role in the canonical graph

Authority tier: Official survey
Provenance: Authoritative
Canonicality: tier 1
Primary for: —
Contributes IDs: —
Name-block matching: trusted
Reconcile profile: default (tier 1)

Schema

What it feeds & emits

Feeds (axes)

Supply

Record kinds

GeochemSummary

Identifier schemes

—

Federated from primary sources. Every fact carries its provenance.

USGS·MSHA·EPA FRS·Wikidata·CEPII BACI·IEA CMO·NREL·BGS·GCAM·HECTOR·PROMMIS

Strata is a product of

© 2026 BrightQuery, Inc. All rights reserved.