Heterosite mineral
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.
Microbial & Biochemical Mechanisms (1)
Abiotic delithiation and lithium uptake by a synthetic heterosite-structure sorbent
redox transformation
Persulfate treatment removed lithium from commercial LiFePO4 to form a source-assigned heterosite-structure FePO4 solid. In separate experiments, thiosulfate-assisted lithiation loaded this synthetic solid with lithium from LiCl solutions, iron-depleted Bruchsal geothermal brine, or a synthetic Neustadt-Glewe-like brine. Diffraction and chemical measurements support structural conversion and lithium uptake, but the products contain residual lithium, substitutions and secondary phases. Reductive intercalation is the authors' interpretation; uptake is not evidence of an isolated pure lithium product.
Experimental Context & Analytical Limits:
Reich2024 used commercial carbon-coated IBUvolt LFP400. Delithiation screening used approximately 1 g in 200 mL at nominal 25 degrees C, with water, NaCl, HCl and oxidant comparisons; reaction times differ among screening arms. Selected kinetics used 0.1 M Na2S2O8. Subsequent lithiation generally used 0.5 M Na2S2O3: pure LiCl experiments had nominal 200 mg/L Li and temperatures 25, 60 or 80 degrees C, while brine experiments used a nominal 60 degrees C setting. Natural Bruchsal feed had been pretreated to remove iron; the second brine was synthetic. Table 2 reports about 155-158 mg/L Li for Bruchsal versus approximately 11 mg/L for the synthetic brine, while figure labels round these to 160 and 10. Kinetic experiments used roughly 5 g sorbent/L over one minute to two weeks; isotherms varied sorbent loading and used three hours for Bruchsal and four hours for synthetic brine. The Bruchsal suspension was stirred, the synthetic one shaken. The workbook separately records nominal treatment temperature and temperatures during pH measurements; these are not asserted to be identical. Blanks and analytical quality controls were included, but independent experimental replication is not clearly established. No organisms were used.
Reich2024 used commercial carbon-coated IBUvolt LFP400. Delithiation screening used approximately 1 g in 200 mL at nominal 25 degrees C, with water, NaCl, HCl and oxidant comparisons; reaction times differ among screening arms. Selected kinetics used 0.1 M Na2S2O8. Subsequent lithiation generally used 0.5 M Na2S2O3: pure LiCl experiments had nominal 200 mg/L Li and temperatures 25, 60 or 80 degrees C, while brine experiments used a nominal 60 degrees C setting. Natural Bruchsal feed had been pretreated to remove iron; the second brine was synthetic. Table 2 reports about 155-158 mg/L Li for Bruchsal versus approximately 11 mg/L for the synthetic brine, while figure labels round these to 160 and 10. Kinetic experiments used roughly 5 g sorbent/L over one minute to two weeks; isotherms varied sorbent loading and used three hours for Bruchsal and four hours for synthetic brine. The Bruchsal suspension was stirred, the synthetic one shaken. The workbook separately records nominal treatment temperature and temperatures during pH measurements; these are not asserted to be identical. Blanks and analytical quality controls were included, but independent experimental replication is not clearly established. No organisms were used.
Curated Evidence Points:
Context_only
Source:
eventoff1972
The natural-crystal experiment on pages 45-49, Tables 2-4 and Figure 1 grounds heterosite independently of the engineered sorbent. It used Mn:Fe approximately 35:65 and found the lithium site essentially vacant. This is structural identity evidence, not a geothermal lithium-extraction experiment.
Support
Source:
reich2024
Table 1 and Figures 1-4, pages 4-8, characterize the commercial precursor and delithiated solid. Lithium decreases from 43 to 1.7 mg/g in the two bulk analyses. The authors assign orthorhombic triphylite and heterosite structures, respectively. Residual Li, nonideal Fe/P chemistry, shifted diffraction peaks and an unidentified reflection near 64.35 degrees 2-theta preclude treating the latter as a demonstrated phase-pure ideal FePO4 endmember.
Support
Source:
reich2024
Sections 3.2-3.4 and Figures 5-11 separate preparation, solution and brine arms. Selected 0.1 M persulfate kinetics released approximately 42-43 mg Li per gram of precursor within one minute, while water released approximately 1-3 mg/g in the screening arms. For natural Bruchsal brine, the kinetic series approached 23 mg Li/g prepared sorbent after three hours; its separate isotherm gave approximately 24-27 mg/g at 2.5-5 g/L. The synthetic low-Li brine gave approximately 1.0 mg/g in the kinetic arm and 1.3 mg/g at 2 g/L in its separate four-hour isotherm. These are source-reported sorbent-normalized loadings, not percentages of purified lithium recovered.
Partial
Source:
reich2024
Figure 8 and section 3.3 show a conditional null: seven-day pure-LiCl experiments at nominal 60 and 80 degrees C did not show lithium uptake, unlike the 25-degree arm. Thiosulfate instability and acidification confound a simple temperature-only interpretation. Figures 1-2 and 9-12 show secondary gypsum/sulfur formation, sodium and sulfur accumulation, and increasing Fe/P release during prolonged reaction. Performance in the early brine experiments is therefore not proof of long-term structural stability, universal selectivity or repeated industrial cycling.
Partial
Source:
reich2024_si
The workbook distinguishes fluid-OES and solid-digestion measurements, so a single analytical basis is not imposed on all reported loadings. Sheets Fig. 9a, Fig. 10 and Fig. 9b, Fig. 10 label kinetic lithium as fluid OES; sheets Fig. 10, Fig. 11a+b and Fig. 10, Fig. 11c+d label isotherm lithium as digestion OES. Bruchsal isotherm cells K9/K10 report about 26.76/23.68 mg/g, while synthetic-brine cell M11 reports about 1.317 mg/g. Some high-loading residual-fluid cells are encoded as zero or less than LOQ; they are not accepted as proof of exactly zero residual lithium or a closed recovery balance. Blank rows with zero sorbent mass also carry load-labelled entries whose normalization is not explained. Published static cell values were inspected without inventing missing formulas or silently replacing the source calculations.
Sources & References
-
ima_2026_09: IMA-CNMNC. The New IMA List of Minerals, September 2026. Heterosite row, PDF page 93, Fe3+(PO4), G, 1826; status definitions page 1.
https://cnmnc.units.it/files/editor/IMA_Master_List_(2026-09).pdf (accessed 2026-10-15) -
handbook_heterosite: Handbook of Mineralogy. Heterosite, complete one-page entry; natural chemistry and orthorhombic Pmnb identity. Secondary authority, older group terminology qualified by Lyalina2023.
https://handbookofmineralogy.org/pdfs/heterosite.pdf (accessed 2026-10-15) -
eventoff1972: Eventoff W, Martin R, Peacor DR (1972). The crystal structure of heterosite. American Mineralogist 57:45-51. Complete seven-page original; experimental section page 46, Tables 2-4 pages 47-48 and Figure 1 page 49 inspected. Separate NAPS structure-factor Table 1, document 01668, was not acquired; no independent re-refinement claimed.
https://www.rruff.net/doclib/am/vol57/AM57_45.pdf (accessed 2026-10-15) -
lyalina2023: Lyalina LM, Selivanova EA, Hatert F (2023). Nomenclature of the triphylite group of minerals. European Journal of Mineralogy 35:427-437. Tables 1-3 and sections 4-6 distinguish present species and historical names; nomenclature reused from round93, not a new oxidation experiment.
https://doi.org/10.5194/ejm-35-427-2023 (accessed 2026-10-15) -
reich2024: Reich R, Eiche E, Kolb J (2024). Delithiation and lithiation of LiFePO4: Implications for direct Li extraction from synthetic solutions and geothermal brines. Desalination 586:117883. Complete eighteen-page original, methods section 2 and subsection 2.1 (PDF page 3), Figures 1-12 and Tables 1-3 inspected.
https://doi.org/10.1016/j.desal.2024.117883 (accessed 2026-10-15) -
reich2024_fulltext: KIT institutional copy of the complete Reich et al. publisher original, CC BY 4.0.
https://publikationen.bibliothek.kit.edu/1000172429/153604117 (accessed 2026-10-15) -
reich2024_si: Official Reich2024 supplementary workbook, fourteen sheets corresponding to Figures 5-12. Native cell values, method labels, censoring, blanks and selected claim-bearing rows inspected; published static values contain no formulas.
https://ars.els-cdn.com/content/image/1-s2.0-S0011916424005940-mmc1.xlsx (accessed 2026-10-15)
Curation History
| Timestamp | Curator | Action | Summary |
|---|---|---|---|
2026-10-15T12:44:57.814050+00:00 |
codex (GPT-6; codex) | CREATE | Added mineral identity and qualified primary abiotic transformation evidence, preserving material provenance, controls, analytical denominators and source limitations; no microbial or inherited criticality claim. |
2026-10-15T12:59:47.637752Z |
codex (GPT-6; codex) | EDIT | Corrected the Reich2024 methods locator to section 2 and subsection 2.1 on PDF page 3, resolving independent F1 and issue 339; scientific statements and the original CREATE remain unchanged. |
Record source: data/records/heterosite.yaml