Redox Transformation Mechanisms

Akaganeite is a distinct iron oxyhydroxide mineral species, listed with formula (Fe(III),Ni(II))8(OH,O)16Cl1.25·nH2O, renamed status (Rn), and IMA number 1962-004 in the September 2026 IMA master list. The experimental abbreviation beta-FeOOH identifies the synthetic phase assignment used by the study; it does not establish the ideal IMA composition or nickel content of that preparation. This record is separate from iron element, other iron oxyhydroxide species, iron-ore commodities, and mixed waste feeds. No constituent criticality designation is inherited.

• Geobacter sulfurreducens PCA

Anilite is the orthorhombic copper sulfide mineral Cu7S4, distinct from digenite, djurleite, chalcocite, covellite, copper element and mixed ores. The September 2026 IMA list gives approved status and approval 1968-030. The accepted experiment concerns natural anilite-bearing grains with intergrown djurleite, not a certified pure mineral feed. This record curates abiotic ferric-sulfate alteration; it does not inherit copper criticality or establish a microbial mechanism.

Antimony (Sb), represented as an element distinct from antimonate feed, sorbed antimonite and sulfide-bearing products. A sediment-inoculated laboratory experiment supports transformation through coupled microbial and chemical reactions under sulfidogenic conditions. The United States 2025 critical-mineral designation names the antimony commodity; it does not designate every Sb compound, host mineral or secondary resource.

Asbolane is a hydrous manganese oxide mineral with variable associated hydroxide cations, listed as grandfathered with historical year 1841 in the September 2026 IMA-CNMNC list. Its listed formula is Mn4+(O,OH)2·(Co,Ni,Mg,Ca)x(OH)2x·nH2O. It is distinct from elemental manganese, cobalt and nickel, from lateritic ore, and from an arbitrary cobalt-doped birnessite preparation. The experiment below uses a synthetic Co/Ni-bearing powder that the source assigns to asbolane by XRD; no independent refinement establishes ideal composition or complete phase purity. No commodity criticality is inherited.

• Geobacter sulfurreducens

Sulfur-rich material recovered from biogas desulfurization, represented by dried powder obtained from a Danish biogas-plant desulfurization unit. Its process origin defines this secondary resource; it is not pure sulfur as an element, a natural sulfur mineral, commercial acid or the battery black mass subsequently leached with its conversion liquor. The selected study does not establish universal residue composition or inherited criticality.

Chlorite denotes a hydrous phyllosilicate group with a hydroxide interlayer, not a single species or the dissolved chlorite anion. The nomenclature authority distinguishes constituent species by composition and structure. The microbial study used a natural Michigamme, Michigan chlorite preparation with residual magnetite and another unresolved iron-bearing impurity. Its author-assigned ferroan clinochlore identity is retained as specimen context, without converting this group owner into a phase-pure clinochlore or chamosite record. No constituent criticality designation is inherited.

• Shewanella oneidensis MR-1

Chromium-bearing waste from chemical processing of chromite ore, distinct from the chromite mineral species and physical-beneficiation tailings. The curated case is a cementitious, high-lime-process residue from a Glasgow waste-fill site that received material from the Rutherglen Chromite Processing Works. High-lime processing oxidized ore Cr(III) to soluble Cr(VI), followed by aqueous extraction. The 2015 study sampled field-moist material from an exploratory borehole during the M74 motorway project and initially identified it tentatively as COPR from its pale granular appearance and high-pH yellow leachate. Subsequent XRF and XRD characterized a mixed residue rather than proving a pure feed. XRD identified cementitious and hydrated phases, including calcite, portlandite, brownmillerite, pyroaurite, hydrogarnet and brucite; remnant chromite was not detected by that assay. Table 4 reports 3.8 wt% Cr in the XRF composition, without loss-on-ignition correction; this is neither a mineral fraction nor a field-wet feed concentration. This record does not confer a constituent element's criticality designation on the residue or assert commercial microbial processing.

• Geobacter sulfurreducens

Chromite is the Fe(II)Cr2O4 mineral species, grandfathered in the September 2026 IMA list with original-description year 1845. It is distinct from elemental chromium, chromate, chromium-bearing spinels of unspecified composition, mixed chromite ores and processing tailings. The natural specimen called chromite in the experiment below was not compositionally or crystallographically characterized in that paper. Its measured Fe(II) change is a specimen-associated observation, not proof of conversion of pure endmember chromite. No criticality designation is inherited from chromium.

• Azospira oryzae PS

Chromium (Cr), represented as an element. Its identity differs from chromate oxyanions, potassium chromate reagent, chromium-bearing precipitates and chromite mineral species. The dated US designation names the chromium mineral commodity and is mapped to its elemental identity here; it is not inherited by every chromium compound or waste.

• Shewanella oneidensis MR-1

Tellurium-containing processing residue described by Bonificio and Clarke as an effluent from processing tellurium from copper anode slime. The experimentally tested material was a dried powder supplied by the Freeport-McMoRan Copper and Gold refinery in El Paso, Texas. This downstream residue is distinct from untreated copper anode slime, copper ore, elemental tellurium and the separate commercial tellurium compounds used in the study. Its bulk elemental composition, mineral phases and original processing conditions were not reported. No criticality-list status is inferred from its constituents or the article's historical discussion of tellurium.

• Pseudoalteromonas

Digenite is a distinct copper sulfide mineral, listed as Cu1.8S by the September 2026 IMA list and as Cu9S5 in the Handbook of Mineralogy. IMA status is approved through 1962 special procedure, not a numbered approval accession. It is distinct from anilite, djurleite, chalcocite, covellite, copper element and mixed copper ores. The curated laboratory study uses synthesized digenite and chemical ferric sulfate; neither constituent criticality nor microbial activity is inferred.

Feroxyhyte is the iron(III) oxyhydroxide mineral species Fe3+O(OH), listed as approved with IMA number 1975-032 in the September 2026 IMA-CNMNC list. The curated experiment used chemically synthesized feroxyhyte, described as delta-prime FeOOH, rather than a natural ore. This mineral identity is distinct from other FeOOH polymorphs, elemental iron and the mixed secondary solids formed during the experiment. No constituent-element criticality or industrial recovery is inferred.

• Shewanella putrefaciens CN-32

Ferrihydrite is an approved mineral species in the September 2026 IMA list, with formula Fe(III)5O7(OH) and approval number 1971-015. The name also occurs in experimental descriptions of poorly crystalline synthetic two-line iron oxyhydroxides; that assay designation does not independently establish ideal IMA formula, natural origin or purity. This record concerns a characterized synthetic nanophase substrate, not iron metal, an ore grade or every Fe(III) oxide. The Ax17 assay is also represented under iron and the paired ferrihydrite/magnetite record; these are substrate/product perspectives on one experiment, not independent replication. No iron criticality designation is inherited.

• Desulfovulcanus ferrireducens

Galena is the PbS mineral species listed as grandfathered in the September 2026 IMA list; its original-description year is unresolved there. It is distinct from elemental lead, anglesite, manufactured PbS reagents and mixed lead ores or flotation concentrates. The experiment below concerns galena within a natural mixed concentrate, not a pure natural endmember. No criticality designation is inherited from lead.

• Acidithiobacillus ferrooxidans

Hauerite is the cubic manganese disulfide mineral MnS2, with pyrite-type structure and grandfathered status in the September 2026 IMA list. It is distinct from the MnS minerals alabandite and rambergite and from elemental manganese. The accepted experiment measures sulfur products during sterile ferric-chloride oxidation of source-identified hauerite. It does not establish a hauerite-specific microbial process, manganese recovery or inherited criticality.

Heterogenite is the cobalt(III) mineral with ideal formula CoO(OH), recorded as approved, 1967 special procedure, in the September 2026 IMA list. The Handbook describes 3R and 2H polytypes; neither is assigned to the experimental ore below. It is distinct from elemental cobalt, other cobalt minerals and an entire copper-cobalt ore. The accepted primary experiment concerns chemical leaching of mixed natural ore whose cobalt-bearing mineral was assigned to heterogenite by QEMSCAN. It does not demonstrate microbial participation, a pure-phase dissolution yield or an inherited criticality designation.

Heterosite is the ferric phosphate mineral with ideal formula Fe3+(PO4), listed as grandfathered by IMA-CNMNC in September 2026 with original-description year 1826. Natural specimens can contain substantial trivalent manganese. It is distinct from lithium-bearing triphylite and Mn3+-dominant purpurite. Eventoff et al. (1972) refined a natural Fletcher Quarry, New Hampshire crystal of approximate composition (Fe0.65Mn0.35)PO4 with an effectively vacant lithium site. The 2023 triphylite-group nomenclature retains heterosite while discrediting ferrisicklerite and sicklerite; the historical oxidation experiment already curated under cmmmech:triphylite is not counted here as a new experiment. The separate Reich et al. (2024) study concerns a synthetic heterosite-structure FePO4 sorbent made from commercial carbon-coated LiFePO4, not mined natural heterosite. Its laboratory lithium uptake from pretreated natural geothermal brine and a separate synthetic brine does not establish purified lithium recovery, natural-ore extraction, microbial activity or industrial deployment. No constituent-element criticality is inherited.

Illite is represented as a mineral group, as designated in the IMA compendium nomenclature table, rather than an ideal single species or an undifferentiated clay commodity. The experimental material is the source-designated IMt-1 illite preparation. Its measured behavior is not transferred from the separate nontronite and montmorillonite studies that reported mixed illite-like transformation products. No phase-pure endmember, universal formula or constituent criticality designation is asserted.

• Shewanella vesiculosa

Jarosite is the potassium ferric hydroxysulfate mineral with ideal formula KFe3(SO4)2(OH)6, with all three iron atoms ferric. The September 2026 IMA list records the species as redefined, 1987 s.p. This record denotes K-jarosite, not the broader jarosite family, natrojarosite, ammoniojarosite, hydroniumjarosite, elemental iron or an industrial jarosite-bearing waste. The experiment below uses a laboratory biosynthesized potassium-jarosite preparation whose bulk composition differs from the ideal endmember. No constituent-element criticality or commercial recovery status is inferred.

• Acidithiobacillus thiooxidans

Lepidocrocite is the Fe(III)O(OH) mineral species listed as approved (A), with 1980 special-procedure history, in the September 2026 IMA master list. The 1980 s.p. entry is not an approval-number CURIE. This species is distinct from goethite, akaganeite, iron element, iron-ore commodities, and the chemically prepared or commercial laboratory feeds discussed below. No iron criticality designation is inherited.

• Shewanella putrefaciens CN-32

Lithiophilite is the lithium manganese(II) phosphate mineral LiMn2+(PO4), listed by IMA-CNMNC in September 2026 as grandfathered with original-description year 1878, not an approval identifier. It is distinct from Fe2+-dominant triphylite, synthetic battery materials of unspecified phase and oxidized lithium-deficient group members. Losey2004 measured natural Mn-rich crystals from the Bennett Quarry, Maine, and Fillow Quarry, Branchville, Connecticut, using microprobe and single-crystal diffraction in orthorhombic space group 62 (Pbnm setting; Handbook Pmnb is another setting). Natural samples contain substitutional Fe and are not pure endmembers. Lithium in that study was constrained or assumed rather than independently measured. The separate Schmid-Beurmann2013 oxidation assay used a laboratory-synthesized, diffraction-assigned LiMnPO4 powder and found no detected phase or lattice change under one specified treatment. That conditional null does not establish universal resistance to lithium dissolution. Neither source demonstrates microbial transformation, isolated lithium recovery or inherited criticality.

Ludlamite is the ferrous phosphate mineral with ideal formula Fe2+3(PO4)2(H2O)4, recorded as grandfathered in the September 2026 IMA list. It is a distinct mineral species from the three-water phosphoferrite and eight-water vivianite. Moore (1971) investigated natural ludlamite crystals from the Palermo number 1 mine in an abiotic heating comparison. The lower-temperature arms retained the starting powder pattern, whereas the 240 degrees C arm gave a ferric product with diffuse diffraction unrelated to the initial mineral. This observation does not identify a pure crystalline product or establish a general transformation temperature for all ludlamite specimens. The ludlamite and phosphoferrite observations curated in this corpus are different mineral arms of the same study, not independent replications. No microbial process, isolated-product recovery or constituent-derived criticality designation is asserted.

Maghemite is the ferric iron oxide mineral commonly written gamma-Fe2O3, distinct from hematite, magnetite, elemental iron and an unresolved magnetic iron-oxide mixture. The September 2026 IMA list gives the vacancy-bearing formula (Fe3+0.67 vacancy0.33)Fe3+2O4 and status Rd, redefined through a 2018 special procedure; this is not an IMA proposal identifier. The curated laboratory study used synthesized nanomaghemite and supports culture-associated reduction toward magnetite-like products, with sulfate-dependent differences and mixed-product limitations. No iron criticality designation, natural-ore extraction yield or industrial deployment is inherited.

• Desulfovibrio sp. J01

The element Mn, distinct from its dissolved oxidation states, ligand complexes, oxide minerals, and Mn-bearing commodities. The US designation below maps to the explicitly named manganese commodity in the 2025 list; it does not assign criticality to every Mn-bearing compound or resource.

• Pseudomonas putida GB-1

Manganite is the manganese(III) oxide hydroxide mineral MnO(OH), listed as grandfathered in the September 2026 IMA-CNMNC list. The year 1826 is its historical date, not an IMA approval accession. It is distinct from elemental manganese, manganese ore, the MnO2 minerals pyrolusite and ramsdellite, and other MnOOH polymorphs. The experiment below used laboratory-prepared material assigned to manganite by the source, not natural ore or a certified phase-pure mineral reference. No criticality designation is inherited from manganese.

• Shewanella sp. MR-4

Metacinnabar is the cubic mercury sulfide mineral beta-HgS, distinct from trigonal cinnabar, hypercinnabar, elemental mercury and unspecified Hg-S precipitates. The September 2026 IMA list gives grandfathered status and original-description year 1870, not a unique approval accession. The curated experiment concerns mercury mobilization and reduction from mineral feed, not microbial formation of this species or a purified recovery product. No mercury or selenium criticality designation is inherited.

• Thiobacillus thioparus

Metavivianite is the approved mixed-valence iron phosphate mineral species Fe2+Fe3+2(PO4)2(OH)2(H2O)6, IMA 1973-049. It is distinct from vivianite, elemental iron or phosphorus, and an unidentified oxidized iron-phosphate mixture. Laboratory abiotic precipitation provides diffraction-supported formation in a mixed product. A separate bacterial enrichment study proposed a metavivianite-like intermediate without diffraction confirmation; that observation is retained as provisional and does not establish formation of the accepted mineral species. No constituent criticality designation or industrial recovery claim is inherited.

The element Mo, distinct from molybdate ions, experimental sodium molybdate, molybdenum-blue products, molybdenite and other Mo-bearing resources. The Canadian designation is the named molybdenum material in its 2024 list; it does not assign criticality to every compound or ore. A laboratory DRY1 culture study supports molybdenum-blue formation consistent with molybdate transformation, without an isolated-metal recovery yield or a chemically resolved product phase.

• gamma proteobacterium DR.Y1

Montmorillonite is a hydrated smectite mineral with generalized formula (Na,Ca)0.3(Al,Mg)2Si4O10(OH)2·nH2O, distinct from nontronite, generic smectite, mixed-layer illite-smectite and bentonite clay resources. The September 2026 IMA list retains the name as grandfathered, dated 1847; this date is not a numbered approval accession. The curated experiment used processed natural Source Clays SWy-2 rather than an ideal pure endmember. No criticality designation is inherited from aluminium, magnesium or other constituents.

• Shewanella oneidensis MR-1

Montroseite is the vanadium oxyhydroxide mineral with ideal formula V3+O(OH), listed as grandfathered (G), original-description year 1953, in the September 2026 IMA list. That year is not a numbered IMA approval. The original Colorado Plateau specimens were iron-bearing, commonly altered and incompletely separated from associated minerals. Single-crystal diffraction assigned the sharp orthorhombic Pbnm lattice to montroseite; the diffuse lattices and much of the original bulk powder pattern represent altered material, subsequently distinguished as paramontroseite or unresolved diffuse A. The historical Fe2+/V4+ compensation model is a chemical interpretation, not a modern site-specific valence measurement. Montroseite is distinct from paramontroseite, elemental vanadium and mixed uranium-vanadium ore. The cited natural evidence does not establish microbial formation, extraction, isolated-product recovery or industrial deployment; criticality is not inherited from vanadium.

Ningyoite is an approved mineral species listed as (U,Ca,Ce)2(PO4)2·1-2H2O in the September 2026 IMA compilation, with status A and special-procedure entry 1962 s.p. Experimental papers use the calcium U(IV)-phosphate formulations CaU(PO4)2·H2O or CaU(PO4)2 for their assigned products; those formulas do not establish every natural specimen's composition. The mineral is distinct from elemental uranium, uramphite, uraninite and molecular U(IV)-phosphate complexes. The observations below concern laboratory products, not a natural ore feed or an industrial recovery process. No criticality designation is inherited from uranium.

• Carboxydothermus ferrireducens
• Desulforamulus reducens MI-1

Nontronite is an iron(III)-rich smectite mineral, distinct from the broader smectite group, montmorillonite and clay commodities. The September 2026 IMA list gives Na0.3Fe3+2(Si,Al)4O10(OH)2·nH2O and approval by a 1962 special procedure; natural interlayer cations and composition vary. The curated material is the source-characterized CMS NAu-2 specimen and its separated size fraction, not every nontronite or a chemically pure ideal endmember. No criticality designation is inherited from constituent iron or other elements.

• Shewanella oneidensis MR-1

Orpiment is the monoclinic As2S3 mineral species, grandfathered in the September 2026 IMA list, whose original-description year is unspecified. It is distinct from elemental arsenic, realgar and amorphous As2S3. The observation below concerns an XRD-assigned secondary component of arsenopyrite leaching residues, not an isolated orpiment feed or recovered product. No criticality designation is inherited from arsenic.

• Acidithiobacillus ferrooxidans

Osmium (Os), distinct from osmium chlorides, oxides, coordination complexes and platinum-group ores or commodities. Australia's 20 February 2024 critical-minerals list includes osmium through its explicitly enumerated platinum-group-elements entry; this grouped designation is not a separate unqualified listing of every osmium-bearing material. Curated microbial evidence is a historical cell-extract experiment with qualified product assignments, not a demonstrated industrial recovery process.

Palladium (Pd), chemical element with atomic number 46. This record concerns laboratory reduction of dissolved Pd(II) to cell-associated elemental Pd(0), not extraction from a palladium mineral or an industrial recovery operation.

• Desulfovibrio desulfuricans

Palygorskite is the fibrous hydrated magnesium-aluminium silicate listed by IMA as (Mg,Al)2Si4O10(OH).4H2O, grandfathered status G, original-description year 1862. That year is not an approval accession. This mineral owner is distinct from a commercial attapulgite clay commodity, the smectite group and other clay specimens in the same experiment. The accepted primary evidence concerns size-separated, chemically cleaned PFl-1 material, not an untreated natural assemblage or an industrial recovery feed. No constituent criticality designation is inherited.

• Shewanella putrefaciens CN-32

Paramontroseite is the orthorhombic vanadium dioxide mineral, ideal VO2, listed as grandfathered (G), original-description year 1955, in the September 2026 IMA list. The year is not a numbered IMA approval. It is structurally distinct from generic VO2 and rutile-type or monoclinic VO2 phases, and chemically distinct from montroseite VO(OH). Evans and Mrose established the natural diffuse-B phase in altered Bitter Creek montroseite crystals using a Pbnm model. The inferred natural weathering relation is distinct from the later laboratory heating of Fe-rich Prachovice paramontroseite. The 2023 specimen is zoned, Al-bearing and nonideal; its refinement favors Fe in a separate tetrahedral site and cannot be substituted for a pure-VO2 endmember or a measurement on the 1950s Colorado specimen. Criticality is not inherited from vanadium, and the curated studies establish no microbial mechanism or industrial recovery.

Phosphoferrite is the ferrous phosphate mineral with ideal formula Fe2+3(PO4)2(H2O)3. The September 2026 IMA list records redefined status under the 1980 special procedure. It is distinct from the more hydrated species vivianite and ludlamite, the Mn-dominant related mineral reddingite, and ferric kryzhanovskite. The historical Hagendorf Sud specimen studied by Moore (1971) contained Mn and Ca and was not a pure synthetic Fe endmember. Laboratory heating produced a source-reported ferric crystalline product with diffraction similarities to the starting material. Later structural work by Moore, Araki and Kampf (1980) corrected substantial indexing and unit-cell errors in the earlier natural kryzhanovskite comparison; this record therefore retains the limited heating observation without treating the earlier cell dimensions, exact structural model or pure-product identity as established. These are abiotic laboratory observations, not microbial extraction or demonstrated industrial recovery. No criticality designation is inherited from iron or phosphorus.

Platinum (Pt). The element is distinct from its experimental dissolved chloro-complexes, the potassium salts used to prepare them, and platinum-bearing minerals or wastes. The US 2025 designation names the platinum commodity individually; it is mapped here to the element without designating every platinum compound or secondary resource as critical. Curated evidence concerns laboratory transformation in the presence of bacterial biomass, with substantial abiotic reduction and no demonstrated isolated-metal yield or industrial use.

• Cupriavidus metallidurans CH34

Plumbojarosite is a lead ferric hydroxysulfate mineral with ideal formula Pb0.5Fe3(SO4)2(OH)6, equivalently PbFe6(SO4)4(OH)12, with ferric iron. The September 2026 IMA list marks the species redefined (1987 s.p.). It is distinct from potassium jarosite, natrojarosite and mixed industrial jarosite residues. The curated experiment used an X-ray-diffraction-characterized synthetic analogue, not a natural ore or industrial waste. No constituent-element criticality or industrial deployment is inferred.

• Shewanella putrefaciens CN-32

Pyrite is the FeS2 mineral species listed with grandfathered status G in the September 2026 IMA compilation. Its row does not provide an approval identifier or a known original-description year. The species is distinct from iron, sulfur, marcasite, pyrrhotite, nickel-bearing substituted experimental phases and mixed ores. Natural specimen material and synthesized FeS2 used in the experiment below are separate assay substrates. No constituent-element criticality designation is inherited.

• Methanococcus voltae A3

Pyrolusite is the MnO2 mineral species in the September 2026 IMA list (status A, 1982 s.p.). The special-procedure entry is not a sequential approval accession. The species is distinct from elemental manganese, unspecified MnO2 polymorphs and source-labelled pyrolusite ores. The accepted experiment below is an explicitly abiotic reaction of characterized commercial beta-MnO2. A microbial ore study was inspected but cannot establish phase-specific microbial causality. No manganese-commodity criticality is inherited.

Naturally occurring deep-ocean sediment enriched in rare-earth elements and yttrium, commonly termed REY-rich mud. This record denotes the heterogeneous geological sediment resource, including pelagic clay with REY-bearing biogenic calcium phosphate grains documented in western North Pacific samples. It is distinct from individual rare-earth elements, a purified rare-earth commodity, an isolated apatite mineral, phosphorite, ferromanganese nodules and rock-surface ferromanganese crusts. Host phases and composition vary among deposits; no single mineral formula or universal grade defines this resource. Collection or physical concentration alone does not make the natural feed a secondary resource. No constituent criticality designation is inherited. A field-proxy study provides qualified evidence for an inferred microbial contribution to natural diagenetic iron transformations and REY redistribution; it does not demonstrate a controlled microbial extraction process, a recovered-metal yield, economic reserves or industrial deployment.

Rhodium (Rh). The element is distinct from the Rh(III) chloride hydrate used as experimental feed, monometallic biomass-supported particles and mixed PdRh nanoparticles. The US 2025 list names the rhodium commodity individually; that designation is mapped to the element without extending it to every Rh-bearing compound, mineral or secondary resource. Curated evidence concerns laboratory transformation in synthetic solutions, not extraction from ore, purified-metal recovery or industrial deployment.

• Geobacter sulfurreducens

Riebeckite is the sodium-iron amphibole species with IMA formula vacancy-Na2(Fe(II)3Fe(III)2)Si8O22(OH)2, redefined under the 2012 special procedure in the September 2026 IMA list. Crocidolite denotes its asbestiform variety; this record does not equate every riebeckite specimen with an asbestos feed, elemental iron, or an asbestos-containing waste. The reviewed laboratory assay used UICC crocidolite reference material as supplied. No criticality designation is inherited from its constituents.

• Deferrisoma palaeochoriense

Selenium (Se), chemical element with atomic number 34. The experimental substrate is soluble selenite, distinct from the element identifier, a selenium mineral, or a secondary resource. Australia's dated selenium material designation is mapped to this element without extending it to salts.

• Shewanella oneidensis MR-1

Naturally occurring quartz-rich sand or disaggregated sandstone used as an industrial-mineral feed, represented here by two distinct English quarry samples. Yahaya's Silica 2 was a purple-red Oakamoor/Moneystone rock sample disaggregated to sand-grade powder; Silica 3 was yellow, uncemented Lower Greensand from Grandcourt near King's Lynn. The latter's XRD was dominated by quartz with minor phases assigned as kaolinite and feldspar. These are heterogeneous geological feeds, not the mineral species quartz, elemental silicon, spent foundry sand or a purity-defined silica product. The two samples' compositions and assay outcomes are not pooled. No constituent's criticality designation is transferred to this resource.

• Shewanella putrefaciens

Silver (Ag). The element identity is distinct from the silver(I) salts and precipitates used in the laboratory experiment below. The dated US designation concerns the silver mineral commodity; it is mapped here to its elemental identity, not inherited by every silver-bearing material.

• Shewanella oneidensis MR-1

Acidic metal-bearing process liquids remaining after removal of oxide scale from steel surfaces. The accepted experiment uses hydrochloric-acid liquor collected from a steel-processing plant's pickling bath, subsequently filtered and diluted with laboratory 9K medium. This liquid feed is distinct from steelmaking slag, mill scale, electroplating-bath effluents, treatment sludge and synthetic iron-salt solutions. It is represented as one process-resource identity, without separate owners for acid recipes or facilities. Evidence here concerns culture-associated iron redox transformation and sediment formation in the hydrochloric-liquor arm; it does not establish performance for every steel-pickling liquor, isolated metal recovery or criticality.

• Acidithiobacillus ferrooxidans

Stibnite is the Sb2S3 mineral species, grandfathered in the September 2026 IMA list with original-description year 1832. It is distinct from elemental antimony, dissolved antimony species, mixed antimony ores and mine wastes. The experiment below used commercial stibnite containing quartz, separately from the study's natural ore samples. No criticality designation is inherited from antimony.

• Paracoccus versutus

Tellurium (Te), chemical element with atomic number 52. The experimental substrate here is soluble potassium tellurite, not a tellurium mineral, commodity feed, or secondary resource.

• Rhodococcus aetherivorans

Thallium (Tl) is an element. Its neutral-atom identifier does not denote dissolved Tl(I), a thallium mineral or a secondary resource. The curated laboratory study concerns release of aqueous thallium from a synthetic, nonideal Tl(I)-bearing jarosite during bacterial ferric-iron reduction. No criticality designation or industrial recovery is inferred.

• Shewanella putrefaciens CN-32

The element Ti, distinct from titanium dioxide phases, titanium-bearing mineral species, alloy formulations and the titanium-metal commodity. The United States 2025 Titanium designation is mapped to this element; it does not designate every titanium compound or establish microbial recovery of metallic titanium. The curated experiment concerns alteration of an oxide film on commercially pure titanium laboratory specimens.

• Shewanella algae

Triphylite is the lithium iron(II) phosphate mineral LiFe2+(PO4), listed by IMA-CNMNC in September 2026 as grandfathered, with original-description year 1834 rather than an approval identifier. It is distinct from Mn2+-dominant lithiophilite and oxidized, lithium-deficient members of the group. Losey2004 characterized natural pegmatite crystals by electron microprobe and single-crystal diffraction in the Pbnm setting of orthorhombic space group 62; Pmnb in the Handbook is another setting. The natural samples are solid solutions, including Mg substitution, not all pure LiFePO4. Lithium was not independently measured in that study: Li2O was assumed for matrix correction and Li-site occupancy fixed during refinement. The accepted transformation study uses a separately characterized natural triphylite specimen with minor sarcopsides visible microscopically, and demonstrates abiotic oxidation with spatially resolved lithium depletion, not microbial weathering or a recovered lithium product. The historical ferrisicklerite product name in the 2013 original is discredited under the 2022-approved nomenclature published in 2023; that publication classifies the studied Tri-77 and Tri-87 products as heterosite. No constituent-element criticality designation is inherited.

Uramphite is a hydrated ammonium uranyl phosphate mineral with formula (NH4)(UO2)(PO4)·3H2O in the September 2026 IMA compilation. Its status G denotes a grandfathered species and 1957 is the original-description year, not a modern approval number. The mineral is distinct from elemental uranium, dissolved uranyl salts and the U(IV)-phosphate product ningyoite. The experiment below concerns an abiotic precipitate assigned to uramphite within laboratory growth medium, not a natural mineral specimen or ore. No uranium criticality designation is inherited.

• Carboxydothermus ferrireducens

Uraninite is the UO2 mineral species listed with grandfathered status G and original-description year 1845 in the September 2026 IMA compilation. It is distinct from elemental uranium, uranyl salts, biomass-bound U(IV) complexes and uranium-bearing ores. The observation below concerns laboratory-formed nanocrystalline UO2 identified as uraninite, not a natural ore feed. No criticality designation is inherited from uranium.

• Shewanella oneidensis MR-1

Violarite is the cubic iron-nickel thiospinel mineral with ideal formula FeNi2S4. The September 2026 IMA list records grandfathered status and original-description year 1924, not a numbered approval. It is distinct from pentlandite, polydymite, greigite, elemental nickel and mixed ores. The accepted study uses violarite broadly for intermediate Fe–Ni thiospinel compositions rather than proving an ideal FeNi2S4 product. Its experiments were abiotic and do not inherit constituent criticality or demonstrate microbial production.

Mixed residual solids from acid leaching in zinc hydrometallurgy, including zinc retained in ferrite, sulfide and other specimen-dependent phases. The accepted studies used separate industrial residues from Hunan and Yunnan, China; their compositions and treatment outcomes are not interchangeable. This processing-generated resource is distinct from elemental zinc, a pure zinc-ferrite phase, zinc calcine before leaching, and zinc-purification waste. Two laboratory abiotic treatments are documented. No criticality designation, microbial mechanism, isolated zinc-product yield or deployment of these particular experimental protocols is inferred.