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Albite mineral

Albite is the triclinic sodium feldspar mineral with ideal formula NaAlSi3O8. The September 2026 IMA list marks it grandfathered (G; historical year 1815), not with a numbered approval accession. It is distinct from the feldspar commodity, the potassium-feldspar family, other plagioclase compositions and mixed ores containing albite. The accepted dissolution evidence concerns source-identified Amelia clevelandite under abiotic laboratory conditions; neither microbial activity nor criticality is inferred from elemental composition.

Microbial & Biochemical Mechanisms (1)

Solution-dependent abiotic dissolution of Amelia albite

other

Flow-reactor experiments measured initially nonstoichiometric Na, Al and Si release followed by approximately congruent dissolution after sufficient reaction time. Dissolution depended on solution composition and renewal rate. A sodium-depleted surface layer and activated surface complexes were proposed from these data; their geometry and molecular identities were not directly established.

Experimental Context & Analytical Limits:
The study used handpicked Amelia albite (clevelandite), ground to 50–100 micrometres, repeatedly acetone-cleaned ultrasonically and dried overnight at 100 degrees C. Each dissolution run used 4 g in a fluidized-bed reactor at room temperature and pressure. HCl solutions supplied acidic conditions; Ba-, Li- or Na-hydroxide/chloride solutions supplied alkaline conditions with the corresponding cation held constant. Separate pH 3 experiments varied added Na, Al or Si and solution flow. Table 1 and Figure 3 follow sequential solution changes on the same solid sample, not independent replicates. Handpicking is reported, but this paper does not supply a new quantitative phase-purity assay.
Curated Evidence Points:
Methods pp.969–970 and Results pp.971–980; Table 1 and Figures 1–8 distinguish the batch back-titration exchange experiment from continuous-flow dissolution. Initial Na release is disproportionately large; renewed transients follow changes in solution chemistry. The alkaline run approaches relatively congruent release, with faster steady dissolution at higher alkaline pH. At pH 3, added Al has a stronger inhibitory effect than Na or Si over the tested ranges; sodium-rich alkaline solutions retard dissolution relative to the lithium-containing comparison.
Figures 4 and 10 estimate hypothetical layer thickness from solution mass balances and assumed reactive surface area; Figures 9 and 11–13 concern thermodynamic or kinetic interpretation, not direct imaging of a uniform film. Discussion pp.980–991 explicitly lacks direct discrimination of hydrogen versus hydronium feldspar and notes prior surface-spectroscopy failures to detect a layer. Preferential attack at defects and a discontinuous layer remain compatible with the observations. The model excludes some smaller solute effects and is not a uniquely demonstrated molecular pathway.
Context_only Source: chou1985
Figure 5 and later model comparisons incorporate the authors' earlier experiments, so these are not independent replications. The discussion contrasts a different potassium-rich Hybla feldspar that did not reach congruent dissolution; that result is not relabelled as an albite control. No organism, biological enhancement, isolated-product recovery or industrial deployment was tested.

Sources & References

  1. ima_2026_09: IMA-CNMNC. The New IMA List of Minerals, September 2026; definitions pp.1–2 and Albite row PDF p.6. Previously acquired official original re-inspected 14 October 2026.
    https://cnmnc.units.it/files/editor/IMA_Master_List_(2026-09).pdf (accessed 2026-10-14)
  2. albite_handbook: Handbook of Mineralogy: Albite, 2001 version 1.2, complete one-page entry; triclinic feldspar and plagioclase-series identity, ideal and calcium-substituted compositions.
    https://www.handbookofmineralogy.org/pdfs/albite.pdf (accessed 2026-10-14)
  3. chou1985: Chou, L.; Wollast, R. (1985). Steady-state kinetics and dissolution mechanisms of albite. American Journal of Science 285(10):963–993. DOI 10.2475/ajs.285.10.963; complete original, methods pp.969–970, Figures 1–13 and Tables 1–2.
    https://doi.org/10.2475/ajs.285.10.963 (accessed 2026-10-14)

Curation History

Timestamp Curator Action Summary
2026-10-14T13:14:52.869476+00:00 codex (GPT-6; codex) CREATE Created albite from dated mineral authorities and the complete original abiotic dissolution study, preserving model uncertainty, source lineage and species boundaries.

Record source: data/records/albite.yaml