Phlogopite mineral
Phlogopite is a magnesium-rich mica mineral species with ideal formula KMg3(AlSi3O10)(OH)2 in the September 2026 IMA list, distinct from generic mica, the biotite grouping, muscovite, potassium and traded potash. The IMA row gives grandfathered status and the historical date 1841, not a numbered approval accession. The experiment curated here used a chemically characterized natural phlogopite specimen containing iron and titanium, not an ideal pure endmember. No criticality designation is inferred from its constituent elements.
Microbial & Biochemical Mechanisms (1)
Fungal-associated phlogopite surface alteration under potassium limitation
bioleaching
Microbial
Associated Organisms:
Paxillus involutus (NCBITaxon:71150)
Phlogopite exposed to Paxillus involutus for 21 days showed surface furrows, fractured or raised layers and clustered deposits relative to pre-exposure images. This supports a bounded fungal-associated weathering interpretation. Potassium concentration in harvested mycelium was not significantly greater than in the potassium-depleted, mineral-free fungal control. Greater aluminium and iron concentrations in harvested material are compatible with mineral interaction but do not alone establish intracellular uptake, element-specific release from phlogopite or a recovered-product yield.
Experimental Context & Analytical Limits:
The reported strain was ATCC 200175, with ITS Sanger identity checking described in SI S2. SI S3 locates the natural phlogopite at Caldara di Manziana near Rome, Italy, and reports SEM-EDX/microprobe composition and no other minerals detected by XRD. Approximately 2 cm2 flakes were ultrasonically cleaned in deionized water and autoclaved at 121 degrees C for 15 minutes. Flakes were placed on sterile cellophane over 30 mL modified Melin–Norkrans agar in 100-by-20 mm Petri dishes, inoculated with three 5 mm plugs from seven-day cultures and incubated for 21 days at 25 degrees C in darkness. The phlogopite arm and mineral-free negative control omitted KH2PO4, with ammonium phosphate adjusted to balance phosphorus against the complete-medium positive control. This does not establish identical nitrogen conditions. Agar, cellophane and potentially the inoculum supplied residual potassium; depleted does not mean potassium-free. Five biological replicates per condition supplied elemental and biomass measurements; five per condition were sequenced, although ten were initially allocated to RNA extraction. This plant-free laboratory assay is not an industrial extraction process or demonstrated nutrient transfer to plants.
The reported strain was ATCC 200175, with ITS Sanger identity checking described in SI S2. SI S3 locates the natural phlogopite at Caldara di Manziana near Rome, Italy, and reports SEM-EDX/microprobe composition and no other minerals detected by XRD. Approximately 2 cm2 flakes were ultrasonically cleaned in deionized water and autoclaved at 121 degrees C for 15 minutes. Flakes were placed on sterile cellophane over 30 mL modified Melin–Norkrans agar in 100-by-20 mm Petri dishes, inoculated with three 5 mm plugs from seven-day cultures and incubated for 21 days at 25 degrees C in darkness. The phlogopite arm and mineral-free negative control omitted KH2PO4, with ammonium phosphate adjusted to balance phosphorus against the complete-medium positive control. This does not establish identical nitrogen conditions. Agar, cellophane and potentially the inoculum supplied residual potassium; depleted does not mean potassium-free. Five biological replicates per condition supplied elemental and biomass measurements; five per condition were sequenced, although ten were initially allocated to RNA extraction. This plant-free laboratory assay is not an industrial extraction process or demonstrated nutrient transfer to plants.
Curated Evidence Points:
Support
Source:
pinzari_2024
Methods 2.1–2.3, Results 3.3 and Figure 1b1–b3 document phlogopite surfaces before and after fungal exposure, including furrows and clustered deposits. The comparison is with initial material, not an aged, fungus-free phlogopite arm. The image does not identify a crystalline secondary mineral or quantify dissolution. Muscovite and vermiculite panels belong to separate substrate arms.
Support
Source:
pinzari_2024_si
Methods S1–S3 and Figure S1 establish the organism-checking procedure, experimental arms, specimen provenance and preparation. The phlogopite structural formula is (Si2.75Al1.25)(Al0.14Mg2.09Fe2+0.49Ti0.17)(K0.98)O10(OH)2, with tetrahedral, octahedral and interlayer groups respectively. This is a specimen composition rather than an ideal endmember. The stated lack of XRD-detected accessory minerals has no reported quantitative trace-phase detection limit. KCl exchange applied only to vermiculite, not to phlogopite.
Partial
Source:
pinzari_2024
Table 3 reports mycelial potassium concentrations of 8.64 ± 2.91 micrograms per gram dry mycelium for phlogopite and 5.52 ± 1.69 for the depleted control (means ± SD, n=5), both statistical group c under ANOVA/Tukey. The apparent numerical increase therefore does not establish enhanced potassium acquisition. Neither these concentrations nor the authors’ extraction/assimilation terminology are a fraction of starting mineral potassium or isolated recovery yield. Methods 2.3 removed mineral flakes before digestion but did not separately mass-balance microscopic carryover, surface-associated material and intracellular elements.
Partial
Source:
pinzari_2024
Table 3 assigns phlogopite-grown harvested material significantly higher aluminium and iron concentrations than both controls, but iron was also supplied by the medium, and the paper acknowledges trace aluminium contamination. These comparisons support interaction, not an element-specific source mass balance. Table 1 gives final pH 2.12 ± 0.09 for phlogopite versus 2.54 ± 0.42 for the depleted control; their statistical groups overlap. No matched aged abiotic mineral arm or pH-matched abiotic arm separates fungal enhancement from chemical weathering in the acidified medium. Table 2 reports differing dry-biomass groups for phlogopite and the depleted control; this does not resolve the nonsignificant potassium-concentration contrast.
Partial
Source:
pinzari_2024
Figures 2–5, Table 5 and Discussion 4.2 show expression responses, including the authors’ proposed organic-acid-related weathering interpretation. They do not provide a knockout, enzyme-specific intervention, measured organic-acid flux or demonstrated causal partition among acid attack, physical damage and redox processes in this assay. The paper reports no significant upregulation of identified potassium-transporter genes versus the depleted control. Earlier Pinzari2022 work is related lineage, not an independently verified replication here. Discussion 4.1 also claims significantly increased aluminium for vermiculite, contrary to its Table 3 group b; that cross-substrate claim is not transferred to phlogopite.
Context_only
Source:
ncbi_paxillus
Taxon 71150 resolves the species name. ATCC 200175 remains the strain reported and checked by the authors; no independent authentication of the culture stock or strain-specific NCBI identifier is asserted.
Context_only
Source:
geo_158973
The series metadata links the same experiment and publication. It supplies provenance rather than another weathering observation. Raw-read reanalysis and gene-level supplemental spreadsheet validation are outside this record’s accepted surface and elemental comparisons.
Sources & References
-
ima_2026_09: IMA-CNMNC. The New IMA List of Minerals, September 2026; definitions pp.1–2 and Phlogopite row, PDF p.171, KMg3(AlSi3O10)(OH)2, G, 1841. Retained official original re-inspected 14 October 2026.
https://cnmnc.units.it/files/editor/IMA_Master_List_(2026-09).pdf (accessed 2026-10-14) -
phlogopite_handbook: Handbook of Mineralogy: Phlogopite, 2001 version 1.2; complete two-page entry, monoclinic mica identity, natural compositional variation and polytypes. Original acquired and inspected 14 October 2026.
https://handbookofmineralogy.org/pdfs/phlogopite.pdf (accessed 2026-10-14) -
pinzari_2024: Pinzari, F.; Cuadros, J.; Saiardi, A.; Humphreys-Williams, E.; Jungblut, A.D. (2024). Bespoke strategies of Paxillus involutus to extract potassium from diverse phyllosilicates. Fungal Biology 128:2341–2354. DOI 10.1016/j.funbio.2024.08.002. Complete fourteen-page published original, all Figures 1–5 and Tables 1–5 inspected. This is the same study as the muscovite and vermiculite records, with a distinct phlogopite arm, not independent replication.
https://doi.org/10.1016/j.funbio.2024.08.002 (accessed 2026-10-14) -
pinzari_2024_si: Pinzari et al. (2024) official supplementary material, original DOCX mmc1; Methods S1–S3, Figures S1–S2 and supplemental-data descriptions, inspected through complete text and all five rendered pages. The phlogopite specimen and preparation are in S3.
https://ars.els-cdn.com/content/image/1-s2.0-S1878614624001065-mmc1.docx (accessed 2026-10-14) -
ncbi_paxillus: NCBI Taxonomy: Paxillus involutus, taxon 71150, species rank; authoritative XML checked 14 October 2026. This is not a strain-specific accession.
https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=71150 (accessed 2026-10-14) -
geo_158973: NCBI Gene Expression Omnibus GSE158973; series metadata checked 14 October 2026, public 3 October 2025 and updated 3 January 2026, linked PMID39653481. Same five-condition, twenty-five-sample experiment as Pinzari2024, not independent replication.
https://www.ncbi.nlm.nih.gov/geo/query/acc.cgi?acc=GSE158973 (accessed 2026-10-14)
Curation History
| Timestamp | Curator | Action | Summary |
|---|---|---|---|
2026-10-14T18:50:50.947663+00:00 |
codex (GPT-6; codex) | CREATE | Created species-scoped phlogopite from the complete Pinzari2024 original and official supplement, retaining shared study lineage, surface alteration, null potassium concentration contrast, specimen chemistry, control limitations and proposed-versus-demonstrated mechanism boundaries. |
Record source: data/records/phlogopite.yaml