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LITHOEN

Deposit

Navan

Also known as Tara Mine

A carbonate-hosted zinc-lead deposit in County Meath, Ireland, named by the USGS Mississippi Valley-type model among its important deposits and classed in the USGS database as carbonate-hosted amagmatic.

World map with twelve small symbols — six filled dark-red circles for porphyry copper deposits in the Andes, western North America, New Guinea and Mongolia, and six open circles with dark outlines for sediment-hosted zinc-lead deposits and one district in North America, Ireland and central Africa — over faint grey plate outlines and a pale coastline.
The twelve records — eleven deposits and one mineral district — for which Lithoen holds a sourced coordinate, over faint plate outlines. Every symbol is the same size: a famous deposit does not get a bigger dot, because symbol size would have to encode a metric and the only metrics available are compiler totals with different definitions in the two databases. Thirteen further deposits in this corpus have no sourced coordinate and do not appear here at all. There is no shading, no interpolation and no density surface. This is a map of records held, and where the symbols cluster is where the compilations looked.

Figure by Lithoen. Plate model PB2002 from Bird (2003), doi:10.1029/2001GC000252; GIS conversion by Hugo Ahlenius, Nordpil, ODC-By 1.0. Made with Natural Earth. Singer, D.A., Berger, V.I., and Moring, B.C., 2008, Porphyry copper deposits of the world: U.S. Geological Survey Open-File Report 2008-1155, doi:10.3133/ofr20081155. Singer, D.A., Berger, V.I., and Moring, B.C., 2009, Sediment-hosted zinc-lead deposits of the world: U.S. Geological Survey Open-File Report 2009-1252, doi:10.3133/ofr20091252. Underlying data remain under their own licences. · LITHOEN-ORIGINAL · Derivative: Generated from published Lithoen spatial records by scripts/generate-maps.ts; no coordinate was edited by hand. Deposit symbols are drawn at a fixed radius. No quantity is encoded in symbol size, because the tonnage figures available are compiler totals whose definitions differ between the two databases and are not comparable with one another.

Classification

recognition basis
authoritativeDatabase
realm
europe

What this record is, and who says so

Recognised on the basis of

Authoritative database

A curated deposit database published by a scientific institution, in which inclusion is itself a documented editorial decision with stated criteria.

A deposit is an occurrence of sufficient size and grade that it might, under the most favourable circumstances, be considered to have economic potential. Lithoen records that a named authority made that judgement. It is not a statement that anything here is recoverable, and it is not a resource or a reserve.

How it is interpreted

A deposit is not a mineral system. A source interprets it as an example of one, and interpretations change while the rock does not.

  • Interpreted as an example of Mississippi Valley-type system

    By — USGS Open-File Report 2009-1252 (carbonate-hosted amagmatic) and the USGS Mississippi Valley-type model, which names Navan among the important deposits of the class.

    The interpretation belongs to the source named in the model qualifier, not to the deposit. Another author may classify this body differently, and the record holds the interpretation rather than replacing the object with it.

Commodities documented here

  • Lead (commodity)documented association

    The source documents the commodity in this deposit and states no economic role. Lithoen records the association and infers nothing about how it would be worked.

  • Silver (commodity)documented association

    The source documents the commodity in this deposit and states no economic role. Lithoen records the association and infers nothing about how it would be worked.

  • Zinc (commodity)documented association

    The source documents the commodity in this deposit and states no economic role. Lithoen records the association and infers nothing about how it would be worked.

Reported figures, and what each one is

A sample assay, a deposit average, a compiler total and a reported reserve are different quantities. Each figure below carries which one it is; none of them is a current resource or reserve.

101 Mt

Compiler total, for modelling

effective 2009-01-01

A sum assembled by a database compiler from production plus reserves plus resources at the lowest available cut-off, so that deposits can be compared in a grade-and-tonnage model. It is not a resource, not a reserve and not production; it is a modelling quantity, and the USGS databases Lithoen reads define their tonnage exactly this way.

The USGS sediment-hosted zinc-lead database gives Navan an ore tonnage of 101 million metric tons — a compiler total of production plus reserves plus resources at the lowest possible cut-off grade, assembled for grade-and-tonnage modelling and not a resource, a reserve or production.

2.1 wt%m Lead

Deposit average

effective 2009-01-01

An average grade attributed to a whole deposit by a compiler, over a tonnage defined by that compiler at a stated cut-off. Not a measurement of anything: a summary of an estimate.

The USGS sediment-hosted zinc-lead database gives Navan an average lead grade of 2.1 percent, over the tonnage the same record holds. A deposit-wide average compiled from the literature, not an assay.

8.3 wt%m Zinc

Deposit average

effective 2009-01-01

An average grade attributed to a whole deposit by a compiler, over a tonnage defined by that compiler at a stated cut-off. Not a measurement of anything: a summary of an estimate.

The USGS sediment-hosted zinc-lead database gives Navan an average zinc grade of 8.3 percent, over the tonnage the same record holds. A deposit-wide average compiled from the literature, not an assay.

The source records behind this

What one row of a published dataset was taken to mean, and why. The original record stays traceable after reconciliation.

  • Sediment-hosted zinc-lead deposits of the world (USGS OFR 2009-1252), record 260

    Named there
    Navan
    The source calls it
    deposit
    Lithoen reads it as
    deposit (stated)

    Read as the deposit the compilers named. The USGS Mississippi Valley-type model separately cites Navan as an important deposit of that class, so the identity is corroborated by a second Tier A source.

    Read and refused

    • grade columns with a value of zero — In both USGS deposit databases a grade of zero means the value was unavailable, not that the grade is zero. Reading it as a measurement would publish a false number.
    • decimal-degree columns beyond the authored precision — The decimal-degree columns carry floating-point residue from the degrees-minutes-seconds columns that were actually authored. The point is emitted at the authored precision instead.

How this is mapped

One published representation of where Navan is. Each is one interpretation, by one identified source, at one scale — not the shape of the thing itself.

  • Representative point

    Point · 1 positionspreferred for publication

    A single position standing for something that is not a point. It exists so a feature can be shown on a map or listed by location, and it asserts NOTHING about extent. A representative point for a 2,000 km province is a label anchor, not a location.

    A representative point for Navan from the USGS sediment-hosted zinc-lead database. The compilers state that a location here "is intended to plot within the alteration zone of deposit which may be kilometers across" — so the point is inside a zone, not the centre of one and not a shaft. This row was authored in degrees, minutes and seconds, giving a position stated to about 30 m.

    Boundary certainty
    ApproximateThe position is known only within a distance much larger than the line width on any map that shows it. Drawing it thinner does not make it better known.
    Status of this geometry
    inferredThe status of the geometry, which need not match the status of what the entity’s claims assert.
    Dataset
    Sediment-hosted zinc-lead deposits of the world (USGS OFR 2009-1252)Singer, D.A., Berger, V.I., and Moring, B.C., 2009, Sediment-hosted zinc-lead deposits of the world: U.S. Geological Survey Open-File Report 2009-1252, doi:10.3133/ofr20091252.

    What was done to this geometry

    • By Lithoen — Rounded to 4 decimal places, the precision the compiler authored: this row was recorded in degrees, minutes and seconds, so the position is stated to about 30 m. The dataset's decimal-degree columns carry more digits, which are conversion residue rather than knowledge.
    • Before it reached Lithoen — All deposit locations were checked by the compilers against Google Earth imagery, and many differ substantially from previously published locations as a result.
    • Before it reached Lithoen — Named bodies within two kilometres were combined into one row by the compilers before Lithoen read it.

How this record is known

5
Settled consensus
Cited as the accepted position of the discipline.

5 of 5 claims on this page cite at least one registered source. Counts describe how each statement is known, not how likely it is to be true.

What Lithoen records

Each claim states how it is known and cites its evidence.

EstablishedClassed carbonate-hosted amagmatic by USGS OFR 2009-1252.

How a source classifies it

The USGS sediment-hosted zinc-lead database classes Navan as carbonate-hosted amagmatic. The compilers describe the scheme as new to that report and built on "the observed rocks reported in maps rather than characteristics that are frequently unobservable in yet-to-be discovered deposits" — an observational classification chosen so it can be applied where little is known, and one classification among possible others.

  • model: USGS Open-File Report 2009-1252, using a classification new to that report.
  • source record: record 260
  • assertion basis: SOURCE_CLASSIFICATION

Evidence support: Supported by the cited evidence 2 sources, single source

Evidence: Singer 2009 Primary authority

Established2.1 wt%m Lead

Reported for this deposit

The USGS sediment-hosted zinc-lead database gives Navan an average lead grade of 2.1 percent, over the tonnage the same record holds. A deposit-wide average compiled from the literature, not an assay.

  • scope: depositAverage
  • definition basis: The dataset’s attribute definitions; a value of zero there means unavailable, not zero.
  • source record: record 260
  • effective date: 2009-01-01
  • assertion basis: SOURCE_REPORTED

Evidence support: Supported by the cited evidence 3 sources, multiple sources, independence unknown

Evidence: Singer 2009 Primary authority; Singer 2008 Primary authority

Established101 Mt

Reported for this deposit

The USGS sediment-hosted zinc-lead database gives Navan an ore tonnage of 101 million metric tons — a compiler total of production plus reserves plus resources at the lowest possible cut-off grade, assembled for grade-and-tonnage modelling and not a resource, a reserve or production.

  • tonnage category: compilerTotalForModelling
  • definition basis: The dataset’s attribute definition for oreton, identical to the porphyry database’s.
  • source record: record 260
  • effective date: 2009-01-01
  • precision note: Effective at the 2009 publication of the database, and never to be described as current.
  • assertion basis: SOURCE_REPORTED

Evidence support: Supported by the cited evidence 2 sources, single source

Evidence: Singer 2008 Primary authority

Established8.3 wt%m Zinc

Reported for this deposit

The USGS sediment-hosted zinc-lead database gives Navan an average zinc grade of 8.3 percent, over the tonnage the same record holds. A deposit-wide average compiled from the literature, not an assay.

  • scope: depositAverage
  • definition basis: The dataset’s attribute definitions; a value of zero there means unavailable, not zero.
  • source record: record 260
  • effective date: 2009-01-01
  • assertion basis: SOURCE_REPORTED

Evidence support: Supported by the cited evidence 3 sources, multiple sources, independence unknown

Evidence: Singer 2009 Primary authority; Singer 2008 Primary authority

EstablishedRecognised by both a Tier A database and a Tier A deposit model.

How a source classifies it

Navan is recognised twice over: the USGS sediment-hosted zinc-lead database includes it as record 260, and the USGS Mississippi Valley-type deposit model names it among the important deposits of that class with its own reference. Two Tier A sources of different kinds — a database and a deposit model — is the corroboration Phase 5 prefers and rarely gets.

  • source record: dataset:usgs-sediment-hosted-zn-pb-deposits-of-the-world record 260
  • assertion basis: SOURCE_CLASSIFICATION

Evidence support: Supported by the cited evidence 3 sources, multiple sources, independence unknown

Evidence: Leach 2010 Primary authority; Singer 2008 Primary authority

In the knowledge graph

Record last updated 2026-09-07. Corrections follow the published corrections policy; superseded claims are retained, never silently edited.