changesite-(Y)

Name and reference

Record the authoritative species description, approval record and reference material used for identification.

1. Which published description and IMA-CNMNC record establish the accepted name and diagnostic criteria? definition
2. Which reference specimen or crystallographic dataset underlies this assignment? provenance

Species versus group

Require species-level evidence beyond a merrillite-group match.

1. Which site-occupancy criteria distinguish changesite-(Y) from magnesiochangesite-(Y), changesite-(Ce) and other relevant phosphates? boundary
2. Do the available measurements support the species name, or only a broader group assignment? measurement

Representative analysis

Treat composition as a measurement of a documented grain region with uncertainty.

1. What Ca, P, Y, Fe, Mg, Na and individual rare-earth concentrations were measured, with detection limits? measurement
2. Could adjacent minerals, inclusions, coatings or compositional zoning explain the reported chemistry? boundary

Occupancy and valence

Preserve the assumptions and uncertainties behind the normalized formula.

1. Which normalization basis and site-allocation rules were used to calculate atoms per formula unit? measurement
2. Are Fe2+ and vacancies independently supported, inferred from charge balance or merely assumed? measurement
3. Would another plausible valence or occupancy interpretation change the species assignment? boundary

Reference structure match

Compare observed diffraction with a cited reference under recorded measurement conditions.

1. Which measured reflections, cell parameters and symmetry constraints support the changesite-(Y) assignment? measurement
2. Which reference dataset was used, and could another phosphate structure fit within the measurement uncertainty? boundary

Single-domain evidence

Relate grain geometry, inclusions and damage to measurement validity.

1. What are the grain dimensions and phase boundaries relative to the beam footprint and interaction depth? measurement
2. Were chemical and structural measurements made on the same domain, and how was that correspondence established? provenance
3. Do fractures, alteration or preparation damage require another measurement region? action

Grain to parent sample

Maintain identifiers through extraction, mounting, subdivision and analysis.

1. Which parent sample, basalt fragment and mount contain or originally contained this grain? provenance
2. Which collection and transfer records substantiate the claimed lunar or other origin? provenance

Formation inference

Record textures and associations before using the grain to infer crystallization or later modification.

1. Which neighbouring phases and contact textures are documented around this grain? measurement
2. What evidence supports late crystallization, liquid immiscibility, shock modification or another formation interpretation for this specimen? provenance
3. Which conclusions belong to the host rock or sample assemblage rather than to changesite-(Y) itself? boundary

Evidence gain and consumption

Compare proposed measurements by discrimination power, spatial resolution and material cost.

1. Would additional diffraction, chemical mapping or valence analysis resolve the present ambiguity? action
2. What grain volume or surface would the method consume or modify, and what reference material would remain? measurement
3. Does the specimen allocation permit the proposed preparation and destructive analysis? action

Preservation envelope

Record observed stability and distinguish mineral-specific evidence from host dust, resin or reagent hazards.

1. Which storage, coating, polishing, irradiation or heating conditions has this grain experienced? provenance
2. What changes in chemistry or structure have been observed after preparation or analysis? measurement
3. Which handling restrictions have documented support for this specimen, and which hazard or stability properties remain unknown? action

Check these first

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these check these first hold for the sense of changesite-(Y) this model covers, and on what evidence? provenance

Identifiers and schemes

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these identifiers and schemes hold for the sense of changesite-(Y) this model covers, and on what evidence? provenance

Standards and regulation

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these standards and regulation hold for the sense of changesite-(Y) this model covers, and on what evidence? provenance

Real-world use

Recalled without web access and unsourced; every item is a lead to verify.

1. Which of these real-world use hold for the sense of changesite-(Y) 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.

1. Which of these neighbouring kinds and how to tell them apart hold for the sense of changesite-(Y) this model covers, and on what evidence? provenance