francevillite
Enable an agent to recognise francevillite, assess the identity and condition of a specimen, and determine which analytical, storage or transfer actions its evidence supports.
Bundle → Layer → Finding → Questions Filled
5 bundles · 9 layers · 14 findings · 26 questions
Species and composition Establish what makes the registered thing francevillite and how measured composition supports that name.
Formula evidence
Separate an ideal mineral formula from the composition measured on a particular grain.
Hydrated uranyl vanadate identity
Francevillite is reported as (Ba,Pb)(UO2)2(VO4)2·5H2O; the model must distinguish that reference composition from analytical results and inferred water content. [Cesbron and Morin, 1968](https://www.persee.fr/doc/bulmi_0037-9328_1968_num_91_5_6260)
- Which cited formula convention defines francevillite, and which constituents can substitute without changing the species assignment? definition
- What grain-specific analysis supports the formula, and which components were calculated rather than measured? measurement
Curienite boundary
Assess the species assignment where barium and lead share the relevant compositional position.
Ba/Pb assignment
Record composition, zoning and uncertainty before applying a sourced francevillite-curienite naming criterion.
- Which current nomenclatural rule assigns this composition to francevillite rather than curienite? boundary
- Do mapped Ba/Pb values indicate one composition, zoned grains or distinct intergrown phases? measurement
Phase recognition Connect the francevillite assignment to structural measurements and spatially located observations.
Structural confirmation
Evaluate diffraction against an identified reference and account for conflicting evidence.
Reference pattern match
Preserve the measured diffraction pattern, reference identity and interpretation rather than recording only a successful match.
- Which measured reflections and cell parameters support a francevillite assignment? measurement
- Which reference dataset was used, and what sample composition and measurement conditions does it represent? provenance
- Could unexplained reflections indicate curienite, another associated phase or transformation during analysis? boundary
Grain-level recognition
Locate observations and analyses on the specimen so evidence from neighbouring phases is not combined.
Same-grain evidence
Tie microscopy, chemistry and structural evidence to the same grain or explicitly defined sampled region.
- Which photographed grain or mapped region supplied each chemical and structural measurement? provenance
- Can the analytical footprint include matrix or an adjacent uranium or barium mineral? boundary
Specimen state and context Represent the condition and geological context of the francevillite-bearing material.
Hydrate preservation
Track environmental and analytical histories that might affect the hydrated phase.
Phase-change evidence
Record observed changes and leave unmeasured stability limits unresolved.
- What temperature, humidity, vacuum or irradiation conditions preceded the present observation? provenance
- What repeat diffraction, spectroscopy or water-loss measurement distinguishes retained francevillite from an altered phase? measurement
- Which examination conditions are supported by evidence of phase preservation? action
Occurrence and mixture
Separate locality evidence and geological association from direct species identification.
Documented mineral occurrence
Record the specimen's collection history, matrix, associated phases and measured francevillite fraction without treating locality as proof.
- Which collection record or publication supports the stated locality and specimen history? provenance
- How much of the examined material is identified francevillite, and how was that fraction determined? measurement
Uranium-bearing specimen actions Connect the specimen's uranium-bearing composition, physical integrity and measured condition to decisions about examination and custody.
Exposure and particle evidence
Keep instrument observations, removable particles and chemical composition distinct.
Specimen-specific assessment
Require documented assessment of the actual specimen before interpreting its handling constraints.
- What radiological measurements exist, with which instrument, calibration, geometry and background? measurement
- Is the francevillite-bearing surface intact or shedding material, and what evidence establishes that state? measurement
- Which proposed examination or sampling actions are supported by the recorded assessment? action
Custody and transfer
Link the mineral specimen to the applicable external decisions about storage, transport or disposal.
Action-specific classification
Record verified identifiers and applicable determinations without borrowing classifications from different uranium compounds.
- Which jurisdiction, activity and specimen measurements govern the proposed storage or transfer decision? boundary
- What documented determination and packaging or custody conditions support that action? action
- Does any cited chemical identifier or hazard record actually cover francevillite rather than another uranium-bearing substance? provenance
Evidence and external alignment What the world already says about this thing, gathered so the model can be checked against it.
Reported evidence
Findings from the breadth pass, kept separate from the structural claims.
Check these first
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these check these first hold for the sense of francevillite this model covers, and on what evidence? provenance
Identifiers and schemes
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these identifiers and schemes hold for the sense of francevillite this model covers, and on what evidence? provenance
Real-world use
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these real-world use hold for the sense of francevillite this model covers, and on what evidence? provenance
Failure modes and hazards
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these failure modes and hazards hold for the sense of francevillite this model covers, and on what evidence? provenance
Regional variation
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these regional variation hold for the sense of francevillite this model covers, and on what evidence? provenance
Neighbouring kinds and how to tell them apart
Recalled without web access and unsourced; every item is a lead to verify.
- Which of these neighbouring kinds and how to tell them apart hold for the sense of francevillite this model covers, and on what evidence? provenance
Classifiers Filled
- Family
- Thing Registry
- Category
- Physical world and living systems
- Entry kind
- thing
- Plane
- PHY
- Domain
- PHY.MAT
What it is Filled
Francevillite is a radioactive, hydrated barium-lead uranyl vanadate mineral, commonly represented by (Ba,Pb)(UO2)2(VO4)2·5H2O, that occurs as a secondary mineral in oxidized uranium deposits.
In scope
- Francevillite identity and its compositional relationship to curienite
- Grain-specific chemistry, structural evidence and identification confidence
- Francevillite abundance, intergrowths and host-matrix relationships
- Hydration, alteration and physical condition of the identified phase
- Specimen provenance and evidence supporting permitted examination or movement
Out of scope
- Curienite and other associated minerals as independent species models
- Uranium or vanadium deposits, reserves and mining operations
- Industrial uranium extraction and ore-processing methods
- Commercial products containing uranium, barium or vanadium compounds
- Radiation instruments and jurisdiction-wide regulatory systems
Why it exists Filled
Enable an agent to recognise francevillite, assess the identity and condition of a specimen, and determine which analytical, storage or transfer actions its evidence supports.
Distinguishing features Filled
- Require grain-specific chemistry compatible with a barium-bearing hydrated uranyl vanadate; the reported francevillite composition permits lead substitution and does not require lead to be present. [Cesbron and Morin, 1968](https://www.persee.fr/doc/bulmi_0037-9328_1968_num_91_5_6260)
- Resolve francevillite versus curienite through measured Ba/Pb site composition and an explicitly sourced species-boundary rule, rather than colour or locality; the two are treated as a mineral series. [Cesbron and Morin, 1968](https://www.persee.fr/doc/bulmi_0037-9328_1968_num_91_5_6260)
- Require diffraction consistent with francevillite as well as compatible chemistry, so a mixture containing separate barium and uranium minerals cannot pass as a single francevillite phase.
- Use colour only as supporting evidence: reported francevillite colours span yellow, orange, green and brown, while its reported structure is orthorhombic. [Handbook of Mineralogy](https://www.handbookofmineralogy.org/pdfs/francevillite.pdf)
What robots and AI may and may not do Filled
Must not
- Advise storing it in living or sleeping areas or within reach of children.
- Advise crushing it or handling it without gloves and hand washing.
- Help ship or sell it without disclosing its radioactivity.
Only with a human decision
- Disposal or cross-border transfer of the specimen.
May
- Describe francevillite and its occurrence in oxidized uranium deposits from mineralogical sources.
- Measure and record a specimen's dose rate for its holder.
Moral aspects Filled
- It exposes holders to radiation, and its lead and vanadium add chemical toxicity.
- Buyers who are not told of the hazard cannot protect their families.
Who is affected
- Collectors and households
- Children
- Transport workers
Owners Filled
Steward
The person or collection that holds a specimen; radiation protection authorities regulate it.
Links to other meta-models Filled
parent
- Q2624432 - registry parent class
What else AI and robots need to interact with it Filled
Identity and identifiers required Filled
- Vercy registry: vr.tr.francevillite
- Wikidata: Q1065441 (https://www.wikidata.org/wiki/Q1065441)
Direct properties required Filled
- Analysed mineral formula: Atoms per formula unit, normalization basis and analytical uncertainty
- Barium versus lead occupancy: Ba and Pb atoms per formula unit; molar Ba/(Ba+Pb), with uncertainty
- Diffraction identification: Measured pattern linked to a cited francevillite reference, matching method and residual unexplained reflections
- Hydration condition: Unmeasured, consistent with reference hydrate, suspected water loss or confirmed transformation; associated temperature and humidity
- Francevillite fraction: Mass percent or mapped area percent, explicitly distinguished and accompanied by method and uncertainty
- Grain and matrix association: Mapped francevillite grains linked to neighbouring phases, matrix and analytical spots
- Surface integrity: Intact, fractured, friable, shedding particles or unknown
- Radiological survey evidence: Instrument-appropriate count rate, dose rate or activity units, with geometry, background, calibration and date
- Identification status: Label-only, visually tentative, chemically supported, structurally supported or jointly confirmed
Recognition required Filled
- Bright yellow scaly crystals or crusts on sandstone or uranium ore.
- Resembles other yellow uranyl vanadates; confirmed by analysis.
Capabilities and actions required Filled
- Compare grain chemistry and diffraction with cited francevillite references and record a qualified identification.
- Flag Ba/Pb compositions requiring review against the curienite boundary.
- Map francevillite separately from matrix and associated mineral phases before interpreting bulk analyses.
- Compare successive observations for particle shedding, water loss or phase transformation.
- Select examination or sampling actions using specimen condition and documented radiological assessment.
- Assemble specimen evidence for a jurisdiction-specific storage or transfer decision.
Hazards and failure modes required Filled
- Emits ionizing radiation and releases radon.
- Powder is toxic if inhaled or swallowed.
Standards and interfaces required Filled
- IAEA Safety Standards SSR-6, Regulations for the Safe Transport of Radioactive Material, International Atomic Energy Agency.
Context of use required Filled
- Francevillite is encountered in oxidized uranium deposits and in mineral collections containing secondary uranium minerals.
- Researchers examine it to identify mineral assemblages and understand uranium and vanadium behavior during weathering.
- Museum and collection work also considers its radioactive composition when documenting, storing or transferring specimens.
Sources Filled
- Wikidata item Q1065441: francevillite - identity and sense of the item
- Wikipedia: Francevillite - general description of the item
Open questions
- What current authoritative nomenclature and site-occupancy rule should resolve borderline francevillite-curienite compositions?
- Which reference diffraction and spectroscopic datasets best distinguish francevillite from closely related or intergrown uranyl vanadates?
- What experimentally established temperature, humidity and vacuum limits preserve francevillite, and which phases form when it changes?
- Which CAS, PubChem or EC identifiers, if any, unambiguously cover the mineral species, and are any hazard classifications specifically applicable to it?
- Does the existing Vercy world-model catalogue already cover francevillite, requiring vr.tr.francevillite to link to that publication?
Machine files
Provenance
thing registry research (pass 2) · unreviewed
Built from: models/things/publications/thing-q1065441/spec.json