Strontianite mineral
Strontianite is the orthorhombic strontium carbonate mineral SrCO3, an aragonite-group species distinct from Sr-substituted calcite, mixed calcium-strontium carbonates, celestine, elemental strontium and commercial strontium salts. The September 2026 IMA list gives grandfathered status and original-description year 1791, not a numbered approval accession. The curated experiment identifies strontianite in a laboratory bacterial coating on printed polymer; no mineral-specific criticality designation or industrial recovery claim is inferred.
Microbial & Biochemical Mechanisms (1)
Culture-associated strontianite coating of printed PLA
biomineralization
Microbial
Associated Organisms:
Sporosarcina pasteurii (NCBITaxon:1474)
Sporosarcina pasteurii DSM 33 cultures produced a carbonate coating on vertically suspended printed polylactide surfaces in a strontium-supplemented urea medium. Powder X-ray diffraction assigned the detached coating to orthorhombic strontianite, with supporting carbonate FTIR bands. The proposed ureolytic setting and coating formation are distinguished from the unresolved molecular nucleation pathway at the polymer surface; the study does not establish lattice-pure product or a strontium extraction efficiency.
Experimental Context & Analytical Limits:
The source identifies the purchased DSMZ organism as S. pasteurii 33, type strain. Black FDM-printed PLA coupons measured 1.5 x 1.5 x 0.1 cm. Initial culture density was reported as 10^8 cells/mL, with 333 mM urea and medium adjusted to pH 8.0 using NaOH. The medium contained casein peptone, soybean peptone and NaCl; the masses listed for those ingredients lack an explicit volume basis. Strontium chloride hexahydrate supplied Sr. The source describes a final alkali-earth-metal concentration of 25 g/L, but its wording does not resolve hydrated-salt mass versus elemental-ion mass; no Sr molarity is inferred. Incubation was static at 30 degrees C for one week in 100 mL sterile flasks; working liquid volume is not specified. Uninoculated controls used the corresponding medium, ions and polymer. Samples were washed in distilled water and air-dried at room temperature; detached coatings were characterized by Cu-Kalpha1 powder XRD, FTIR, SEM and polarized microscopy. The study reports triplicate coating-mass experiments, but does not define the uncertainty convention for its reported plus/minus values. Reagent-salt flasks and small coupons are laboratory materials synthesis, not ore processing, radionuclide remediation or industrial deployment.
The source identifies the purchased DSMZ organism as S. pasteurii 33, type strain. Black FDM-printed PLA coupons measured 1.5 x 1.5 x 0.1 cm. Initial culture density was reported as 10^8 cells/mL, with 333 mM urea and medium adjusted to pH 8.0 using NaOH. The medium contained casein peptone, soybean peptone and NaCl; the masses listed for those ingredients lack an explicit volume basis. Strontium chloride hexahydrate supplied Sr. The source describes a final alkali-earth-metal concentration of 25 g/L, but its wording does not resolve hydrated-salt mass versus elemental-ion mass; no Sr molarity is inferred. Incubation was static at 30 degrees C for one week in 100 mL sterile flasks; working liquid volume is not specified. Uninoculated controls used the corresponding medium, ions and polymer. Samples were washed in distilled water and air-dried at room temperature; detached coatings were characterized by Cu-Kalpha1 powder XRD, FTIR, SEM and polarized microscopy. The study reports triplicate coating-mass experiments, but does not define the uncertainty convention for its reported plus/minus values. Reagent-salt flasks and small coupons are laboratory materials synthesis, not ore processing, radionuclide remediation or industrial deployment.
Curated Evidence Points:
Support
Source:
natalio2024
Experimental Section, Results and Discussion, Figure 3a-c middle panels and Figure 4a-b Sr panels support coating formation, diffraction-based strontianite assignment, carbonate spectroscopy and coating morphology. Reported coating mass is 36 +/- 3 mg by substrate mass difference, and SEM-derived thickness is 45 +/- 6 micrometres. These are coating measurements, not a pure SrCO3 mass balance or recovered-Sr yield. The 18 +/- 2 nm value is a Debye-Scherrer crystallite-size estimate, not a directly measured particle diameter. Calcium-polymer comparisons in Figures 1-2 and their growth curves are separate experiments and are not assigned to Sr.
Support
Source:
natalio2024_si
Figure S4 on p. S7 shows washed and dried PLA surfaces after incubation without S. pasteurii but with the respective Ba, Sr or Mg supplementation and 333 mM urea; no coatings were observed. This is a no-cell comparison, not a matched-pH chemical precipitation or urease-inhibition control. Figures S1-S3 concern calcium carbonate and do not establish Sr-phase identity.
Partial
Source:
natalio2024
The statement about finding no entrapped cells occurs in the calcium/polymer discussion and is not transferred to the Sr coating. Biomolecule deposition, epitaxy and polymer surface chemistry remain unresolved explanations for coating nucleation. No enzyme knockout, inhibition series or pH-matched cell-free phase comparison establishes the unique causal pathway. No solution-Sr mass balance, quantified phase purity, coating durability or industrial performance is reported. The printed 25 g/L dosing basis remains ambiguous. The Figure 3a caption gives a 0.375 micrometre scale bar for centimetre-scale coupons; the explicit coupon dimensions, not this inconsistent unit, are used here.
Partial
Source:
natalio2024
Thermal interpretations are excluded from accepted transformation claims: the Experimental Section specifies heating to 800 degrees C, whereas Figure 4c-d and the discussion extend beyond 1000 degrees C. The discussion also invokes a rhombohedral-to-hexagonal transformation despite the diffraction assignment to orthorhombic strontianite. These internal inconsistencies limit the thermal interpretation without erasing the independently reported ambient-condition coating diffraction.
Sources & References
-
ima_2026_09: IMA-CNMNC. The New IMA List of Minerals, September 2026; definitions pp. 1-2 and Strontianite row PDF p. 207, Sr(CO3), G, 1791. Previously acquired dated authority re-inspected on 14 October 2026.
https://cnmnc.units.it/files/editor/IMA_Master_List_(2026-09).pdf (accessed 2026-10-14) -
handbook: Handbook of Mineralogy. Strontianite, version 1, 2001-2005; complete one-page identity entry, orthorhombic SrCO3 and aragonite-group membership.
https://www.handbookofmineralogy.org/pdfs/strontianite.pdf (accessed 2026-10-14) -
natalio2024: Natalio, Filipe and Maria, Raquel (2024). Microbial Biomineralization of Alkaline Earth Metal Carbonates on 3D-Printed Surfaces. ACS Applied Materials & Interfaces 16(5):6327-6336. DOI 10.1021/acsami.3c13665; complete primary text, Experimental Section and Figures 1-4, especially Figure 3 middle panels and Figure 4 Sr panels. PMID 38205804; PMCID PMC10859896.
https://doi.org/10.1021/acsami.3c13665 (accessed 2026-10-14) -
natalio2024_si: Natalio and Maria (2024), Supporting Information, am3c13665_si_001.pdf, all seven pages. Figure S4 on p. S7 documents uninoculated Sr controls; S2 is a blank page. Figshare article 24981775, file 43996393.
https://doi.org/10.1021/acsami.3c13665.s001 (accessed 2026-10-14) -
dsm33: DSMZ catalogue: Sporosarcina pasteurii DSM 33, type strain, strain designation 22.
https://www.dsmz.de/collection/catalogue/details/culture/DSM-33 (accessed 2026-10-14) -
ncbi1474: NCBI Taxonomy 1474, Sporosarcina pasteurii, species; species identifier does not uniquely identify DSM 33.
https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=1474&mode=Info (accessed 2026-10-14)
Curation History
| Timestamp | Curator | Action | Summary |
|---|---|---|---|
2026-10-14T12:27:08.168689+00:00 |
codex (GPT-6; codex) | CREATE | Created strontianite mineral identity and primary laboratory biomineralization evidence with explicit phase, control, measurement and deployment limits; independent scientific review pending. |
2026-10-14T12:33:15.975357+00:00 |
codex (GPT-6; codex) | EDIT | Address independent review and issue 229: confine the no-entrapped-cell observation to its calcium/polymer context rather than transferring it to Sr coatings; preserve supported Sr phase evidence and controls. |
Record source: data/records/strontianite.yaml