CMMMech
CMMMech > Mineral > Forsterite

Forsterite mineral

Forsterite is the Mg2(SiO4) mineral species, grandfathered in the September 2026 IMA list. This species is distinct from elemental magnesium or silicon and from generic magnesium-bearing rocks or commercial mineral mixtures. No constituent criticality is inherited. This record and the companion talc record curate different substrates in the same Cai 2013 experiment, not independent studies.

Microbial & Biochemical Mechanisms (1)

Culture-associated forsterite dissolution with secondary magnesium oxalate formation

bioleaching Microbial

Associated Organisms: Aspergillus niger (NCBITaxon:5061)

Growing Aspergillus niger cultures with a forsterite feed contained dissolved magnesium and yielded precipitate assigned by the authors to glushinskite. Chemical oxalate controls also dissolved forsterite; the result supports conditional fungal-associated mineral transformation rather than microbial necessity or magnesium-metal recovery.

Experimental Context & Analytical Limits:
The reported Aspergillus niger strain has no collection accession in the inspected paper; NCBI:5061 resolves only the species. Mineral powders were washed and sonicated, exposed to 0.1 mM HCl for one hour, rinsed and air-dried; feed XRD purity is reported but its patterns are not shown. In the selected Mg-source comparison, minus-200-mesh particles supplied 0.01 mol Mg to 95 mL Czapek-based medium plus 5 mL inoculum at 10^7 spores/mL. Initial pH was adjusted to 8.15; growing cultures were shaken at 150 rpm and 30 degrees C for ten days. The separate particle-size and filtered-MgSO4-supernatant experiments are not pooled with this comparison.
Curated Evidence Points:
Table 1 reports final supernatant Mg of 1.854 x 10^-2 mol/L with forsterite versus 3.121 x 10^-4 mol/L with talc, measured by ICP-AES. Table 2 gives forsterite abiotic-control Mg at 1.32, 5.09 and 6.10 mM with initial oxalic acid of 0, 100 and 200 mM respectively after ten days. Results p305 assign the forsterite-culture precipitate in Figure 3a to monoclinic glushinskite; the talc arm had no recovered secondary mineral after ten days.
Initial acid doses in the abiotic comparison do not reproduce the culture pH and metabolite trajectories, so the data do not isolate oxalate from other fungal products or proton effects. No replicate counts or measurement uncertainties are specified for Tables 1-2 in the inspected article. Supernatant Mg remaining after precipitation is not a total dissolution or isolated-product yield. Feed purity and product identity are the published analytical assignments, not independently reprocessed diffraction data. The experiment is laboratory-scale and does not establish industrial deployment.

Sources & References

  1. ima_2026_09: IMA-CNMNC. The New IMA List of Minerals, September 2026; PDF page 77, Forsterite row, and pages 1-2 definitions and terms.
    https://cnmnc.units.it/files/editor/IMA_Master_List_(2026-09).pdf (accessed 2026-10-11)
  2. cai_2013: Cai, Xiao, Huang, Li and Zhou (2013). Solubilization of Magnesium-Bearing Silicate Minerals and the Subsequent Formation of Glushinskite by Aspergillus niger. Geomicrobiology Journal 30(4):302-312. DOI 10.1080/01490451.2012.688924; methods pp303-304, Tables 1-2, Results pp304-305 and Discussion pp307-308.
    https://doi.org/10.1080/01490451.2012.688924 (accessed 2026-10-11)
  3. ncbi_niger: NCBI Taxonomy 5061 - Aspergillus niger, species rank; taxonomy XML inspected 11 October 2026.
    https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=5061&mode=Info (accessed 2026-10-11)

Curation History

Timestamp Curator Action Summary
2026-10-11T10:24:35.653580+00:00 codex (GPT-6; codex) CREATE Created forsterite species record with bounded fungal dissolution and abiotic controls.

Record source: data/records/forsterite.yaml