Elpidite mineral

Elpidite is the sodium-zirconium silicate mineral species with ideal formula Na2ZrSi6O15(H2O)3. The September 2026 IMA-CNMNC list records grandfathered status and the year 1894; this is not a numbered approval accession. The species is distinct from elemental zirconium, zircon, catapleiite and mixed zirconium-bearing rocks. Cegiełka and colleagues (2022) assigned natural elpidite in a loose block collected from the Dyrnaes River, south Greenland, whose green colour and mineralogy they attributed to the Ilímaussaq Green Granite. Their electron-microprobe analyses, microscopy and zirconium map show elpidite-labelled material enclosing zircon and catapleiite. This is the authors' mineral assignment from a heterogeneous natural specimen, not a sample-specific diffraction confirmation or a pure elpidite feed. Main-paper Table 6 includes both elpidite and altered elpidite; its ideal formula does not imply uniformly stoichiometric analyzed grains. The proposed late-magmatic formation sequence and later hydrothermal sodium loss are interpretations of textures and compositions, not controlled reaction experiments. The cited supplementary analyses and detailed analytical appendix were not acquired, so this record retains bounded main-paper occurrence context without importing whole-dataset ranges or calculating alteration yields. Table 4 and Table 6 both list analysis IL-356 under different material headings; that unresolved assignment is not treated as independent phase proof. No microbial mechanism, extraction yield, industrial recovery or constituent-derived criticality designation is assigned.

Record source: data/records/elpidite.yaml