Chlorapatite mineral
Chlorapatite is the chlorine-dominant apatite mineral species Ca5(PO4)3Cl, distinct from hydroxylapatite, fluorapatite, pyromorphite, generic apatite and mixed phosphate-rock resources. The September 2026 IMA list marks it renamed with 2010 s.p.; this special-procedure notation is not a new-mineral accession. The accepted experiment used a characterized synthetic analogue as a bacterial nutrient-source comparison. Its findings are not inherited from the pyromorphite dissolution arm or from elemental phosphorus criticality.
Microbial & Biochemical Mechanisms (2)
Bacterial growth with chlorapatite as the added phosphate source
other
Microbial
Associated Organisms:
Pseudomonas putida (NCBITaxon:303)
Pseudomonas putida cultures showed limited growth in phosphate-deficient medium containing synthetic chlorapatite. The observation supports nutrient accessibility in the tested system; it does not quantify bacterial enhancement of chlorapatite dissolution or demonstrate phosphorus recovery.
Experimental Context & Analytical Limits:
Topolska et al. synthesized the source-assigned chlorapatite by heating 0.5 g commercial synthetic hydroxylapatite with 0.5 g CaCl2 at 950 degrees C for 12 h. Table 1 diffraction spacings and Figure 1b SEM-EDS support the assigned phase; the reported particle range was 10-80 micrometres. The paper reports pure chlorapatite, but gives neither a quantitative minor-phase detection limit nor a complete chlorapatite wet-chemical analysis; the separately measured Pb5.09(PO4)2.96Cl formula is for pyromorphite only. Portions of 0.05 g were heated at 180 degrees C for 3 h before use; unchanged XRD/SEM-EDS after heating is asserted as data not shown. Experiments used 100 mL medium in 500 mL flasks, triplicates, 21 +/- 1 degrees C, 100 rpm and 305 h. MP+ contained 0.5 g/L K2HPO4, 5 g/L disodium succinate, 6.5 g/L glycerol, salts and source-reported 30 mM FeEDTA; MP- omitted K2HPO4. Initial pH was adjusted to approximately 7.3. The unusual FeEDTA specification is retained as reported, not silently corrected. E.I control 2 used source-named P. putida IBPRS KKP 1136, earlier identified by numerical taxonomy. Cells were grown to OD600 0.8, centrifuged, resuspended in the experimental solution and inoculated 1:100. Optical density was measured at 600 nm with settled mineral particles; source controls included no-mineral cultures and pyromorphite-containing cultures in MP+ and MP-. No killed-cell arm or direct phosphorus tracer was reported.
Topolska et al. synthesized the source-assigned chlorapatite by heating 0.5 g commercial synthetic hydroxylapatite with 0.5 g CaCl2 at 950 degrees C for 12 h. Table 1 diffraction spacings and Figure 1b SEM-EDS support the assigned phase; the reported particle range was 10-80 micrometres. The paper reports pure chlorapatite, but gives neither a quantitative minor-phase detection limit nor a complete chlorapatite wet-chemical analysis; the separately measured Pb5.09(PO4)2.96Cl formula is for pyromorphite only. Portions of 0.05 g were heated at 180 degrees C for 3 h before use; unchanged XRD/SEM-EDS after heating is asserted as data not shown. Experiments used 100 mL medium in 500 mL flasks, triplicates, 21 +/- 1 degrees C, 100 rpm and 305 h. MP+ contained 0.5 g/L K2HPO4, 5 g/L disodium succinate, 6.5 g/L glycerol, salts and source-reported 30 mM FeEDTA; MP- omitted K2HPO4. Initial pH was adjusted to approximately 7.3. The unusual FeEDTA specification is retained as reported, not silently corrected. E.I control 2 used source-named P. putida IBPRS KKP 1136, earlier identified by numerical taxonomy. Cells were grown to OD600 0.8, centrifuged, resuspended in the experimental solution and inoculated 1:100. Optical density was measured at 600 nm with settled mineral particles; source controls included no-mineral cultures and pyromorphite-containing cultures in MP+ and MP-. No killed-cell arm or direct phosphorus tracer was reported.
Curated Evidence Points:
Support
Source:
topolska_2014
Table 2 E.I and Figure 2b-c show growth with chlorapatite in MP-, whereas the no-mineral MP- comparison showed no sustained culture growth. Growth remained much lower than nutrient-rich cultures. The accepted result is the optical-density phenotype, without converting it to viable counts, biomass yield or a phase-specific phosphorus extraction percentage.
Partial
Source:
topolska_2014
Figure 2a shows no apparent mineral-dependent growth advantage in phosphate-rich MP+ within reported triplicate variability. The chlorapatite comparison therefore concerns phosphate limitation and does not establish a general microbial growth benefit.
Partial
Source:
topolska_2014
Table 2 E.II and Table 3 provide solution-chemistry results for chlorapatite only in uninoculated controls. The biotic phosphate and Pb release series and rising-pH observations in Figures 3-5 concern pyromorphite. They cannot be relabeled as a chlorapatite biotic dissolution series. Abiotic phosphorus release can supply the nutrient used by the cultures; enhanced chlorapatite dissolution, acidification and a specific enzyme or chelator are not established.
Partial
Source:
topolska_2014
The two mineral substrates differed in composition and particle-size range and were not matched by surface area. Their culture-growth contrast is not a normalized dissolution-rate comparison. The study was a laboratory synthetic-mineral experiment and does not measure soil performance, isolated product recovery or long-term stability.
Context_only
Source:
ncbi_putida
NCBI 303 verifies the species label only; it does not authenticate the numerical-taxonomy assignment or stock identity of IBPRS KKP 1136.
Abiotic phosphate release in nutrient-medium controls
other
Synthetic chlorapatite released phosphorus into the phosphate-deficient abiotic control. This explicitly nonmicrobial observation provides an alternative supply pathway for the growth experiment.
Experimental Context & Analytical Limits:
Topolska et al. synthesized the source-assigned chlorapatite by heating 0.5 g commercial synthetic hydroxylapatite with 0.5 g CaCl2 at 950 degrees C for 12 h. Table 1 diffraction spacings and Figure 1b SEM-EDS support the assigned phase; the reported particle range was 10-80 micrometres. The paper reports pure chlorapatite, but gives neither a quantitative minor-phase detection limit nor a complete chlorapatite wet-chemical analysis; the separately measured Pb5.09(PO4)2.96Cl formula is for pyromorphite only. Portions of 0.05 g were heated at 180 degrees C for 3 h before use; unchanged XRD/SEM-EDS after heating is asserted as data not shown. Experiments used 100 mL medium in 500 mL flasks, triplicates, 21 +/- 1 degrees C, 100 rpm and 305 h. MP+ contained 0.5 g/L K2HPO4, 5 g/L disodium succinate, 6.5 g/L glycerol, salts and source-reported 30 mM FeEDTA; MP- omitted K2HPO4. Initial pH was adjusted to approximately 7.3. The unusual FeEDTA specification is retained as reported, not silently corrected. E.II control 2 contained no added bacteria. Solution samples were centrifuged and 0.2-micrometre filtered before ICP-MS analysis. Phosphate-rich controls already contained dissolved phosphate; their final total P is not all mineral-derived.
Topolska et al. synthesized the source-assigned chlorapatite by heating 0.5 g commercial synthetic hydroxylapatite with 0.5 g CaCl2 at 950 degrees C for 12 h. Table 1 diffraction spacings and Figure 1b SEM-EDS support the assigned phase; the reported particle range was 10-80 micrometres. The paper reports pure chlorapatite, but gives neither a quantitative minor-phase detection limit nor a complete chlorapatite wet-chemical analysis; the separately measured Pb5.09(PO4)2.96Cl formula is for pyromorphite only. Portions of 0.05 g were heated at 180 degrees C for 3 h before use; unchanged XRD/SEM-EDS after heating is asserted as data not shown. Experiments used 100 mL medium in 500 mL flasks, triplicates, 21 +/- 1 degrees C, 100 rpm and 305 h. MP+ contained 0.5 g/L K2HPO4, 5 g/L disodium succinate, 6.5 g/L glycerol, salts and source-reported 30 mM FeEDTA; MP- omitted K2HPO4. Initial pH was adjusted to approximately 7.3. The unusual FeEDTA specification is retained as reported, not silently corrected. E.II control 2 contained no added bacteria. Solution samples were centrifuged and 0.2-micrometre filtered before ICP-MS analysis. Phosphate-rich controls already contained dissolved phosphate; their final total P is not all mineral-derived.
Curated Evidence Points:
Support
Source:
topolska_2014
Table 3 gives final total filtered-solution P of 119 +/- 10.7 micromolar in abiotic MP- with chlorapatite and 2796 +/- 9 micromolar in abiotic MP+ with chlorapatite, reported as triplicate standard deviations. These are endpoint solution concentrations after 305 h, not bacterial release measurements, mineral conversion fractions or isolated P-product yields.
Partial
Source:
topolska_2014
Starting phosphate in MP+ contributes to its final P concentration. The study does not report a complete chlorapatite Ca/P mass balance or isolate a recovered phosphorus product. Table 3 is part of the same experiment used under lead and pyromorphite, not independent replication.
Sources & References
-
ima_2026_09: IMA-CNMNC. The New IMA List of Minerals, September 2026. Definitions pp 1-2 and Chlorapatite row p43, Rn, 2010 s.p. Official list reopened and retained original row visually inspected 14 October 2026.
https://cnmnc.units.it/files/editor/IMA_Master_List_(2026-09).pdf (accessed 2026-10-14) -
chlorapatite_handbook: Handbook of Mineralogy. Chlorapatite. Complete one-page identity entry; Cl-dominant species and polymorph context, not an exact symmetry assignment to the experimental powder.
https://www.handbookofmineralogy.org/pdfs/chlorapatite.pdf (accessed 2026-10-14) -
topolska_2014: Topolska, Justyna; Latowski, Dariusz; Kaschabek, Stefan; Manecki, Maciej; Merkel, Broder; Rakovan, John (2014; online 20 July 2013). Pb remobilization by bacterially mediated dissolution of pyromorphite Pb5(PO4)3Cl in presence of phosphate-solubilizing Pseudomonas putida. Environmental Science and Pollution Research 21:1079-1089. DOI 10.1007/s11356-013-1968-3; PMC3880484. Complete 11-page retained original re-read with chlorapatite comparisons in Tables 1-3 and Figures 1-2 independently inspected. Same study also represented under lead and pyromorphite.
https://doi.org/10.1007/s11356-013-1968-3 (accessed 2026-10-14) -
ncbi_putida: NCBI Taxonomy 303, Pseudomonas putida, species. Official XML rechecked 14 October 2026. Species identity does not independently verify strain IBPRS KKP 1136.
https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=303 (accessed 2026-10-14)
Curation History
| Timestamp | Curator | Action | Summary |
|---|---|---|---|
2026-10-14T11:27:17.455877+00:00 |
codex (GPT-6; codex) | CREATE | Created chlorapatite mineral record with primary experimental evidence, exact phase and assay boundaries, controls and unresolved causal limits. |
Record source: data/records/chlorapatite.yaml