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Opoka

carbonate-siliceous marine sedimentary rock

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General referenceInterpretive dossier study · Crown Archives visual atlas
Record originEnglish Wikipedia
Text licenseCC BY-SA 4.0
Source revisionMay 25, 2026
Entity authorityQ4335387 ↗
Source-derived summary

Opoka is a carbonate-siliceous marine sedimentary rock. It was formed during the Upper Cretaceous epoch and mainly found in the Great European Plain regions.

Opoka was first described in literature by Georg Gottlieb Pusch in 1833, who named it as Polnische Opoka.

Editorial summary

“Opoka” enters the record as carbonate-siliceous marine sedimentary rock. Crown Archives preserves that source wording while asking what Opoka, carbonate-siliceous and marine can confirm, complicate or overturn.

Editorial reviewA practical starting point whose main value is the path it opens into stronger specialist and primary sources. The current lead gives the account dated anchors—1833—that can be checked directly. The selected authority fields contribute no independent date. Its strongest next move is a source search built around Opoka, carbonate-siliceous and marine.
Editorial analysis

Why this record matters

“Opoka” is worth following because a concise public description often conceals a longer documentary argument. Here, Opoka, carbonate-siliceous and marine provides the most credible route into that argument.

Evidence profile

Named sources, stable identifiers and responsible institutions provide the strongest route from overview to verifiable evidence. The source revision retrieved here is dated May 25, 2026. The linked authority identifier is Q4335387. None of the 0 selected statements returned an explicit reference. The first chronological checks are 1833.

Critical limits

Overview language is designed for orientation and should not be treated as a substitute for the evidence cited beneath it. The lead is largely declarative, so disagreement and counter-evidence require a deliberate search beyond the opening account. Authority statements aid reconciliation but still require their own references, qualifiers and ranks to be checked.

How to read it

Use the entry as an orientation point, then follow its citations and revision history. Names, dates and institutional relationships should be checked against the original record.

Best used for
  • Subject orientation
  • Search vocabulary
  • Locating named sources
Verify next

The closest primary source, responsible institution and strongest cited specialist reference.

Three-step research path

  1. Establish the record: confirm the title “Opoka”, its source revision and the description used here.
  2. Expand the search: follow Opoka primary sources, Opoka archive and Opoka research across catalogues and specialist indexes.
  3. Test the account: compare the strongest cited source with the responsible institution’s current record and note any disagreement.

Questions for further research

  1. Which source most directly establishes the central claim about “Opoka”?
  2. What terminology or title could unlock a more precise catalogue search?
  3. Which institution is responsible for the underlying evidence?
Subject index

Search terms from this dossier

Source & attribution

This entry incorporates text from “Opoka” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.