Kainotropite, Cu4Fe3+O2(V2O7)(VO4), a new mineral with a complex vanadate anion from fumarolic exhalations of the Tolbachik volcano, Kamchatka, Russia
Bibliographic record
Abstract
ABSTRACT The new mineral kainotropite Cu4Fe3+O2(V2O7)(VO4) was found in sublimates of fumaroles related to the Tolbachik volcano, Kamchatka, Russia. The holotype specimen originates from the Yadovitaya fumarole at the Second scoria cone of the Northern Breakthrough of the Great Tolbachik Fissure Eruption; associated minerals are hematite, langbeinite, calciolangbeinite, tenorite, piypite, lyonsite, rutile, pseudobrookite, sanidine, and lammerite. In paleo-fumarolic deposits of Mountain 1004 kainotropite is associated with diopside and hematite. It forms prismatic crystals up to 0.2 × 0.2 × 0.5 mm3, isolated or combined in clusters up to 0.7 mm across. Kainotropite is iron-black to reddish-black, with semi-metallic luster. Dcalc is 4.10 g/cm3. In reflected light, kainotropite is grey, weakly anisotropic. The reflectance values [Rmax–Rmin,% (λ, nm)] are: 18.3–17.3 (470), 17.3–16.3 (546), 16.9–15.7 (589), 16.3–15.1 (650). The chemical composition of the holotype sample (wt.%, electron microprobe) is: CuO 46.69, Al2O3 1.40, Fe2O3 10.04, TiO2 0.32, V2O5 37.58, As2O5 2.55, MoO3 0.76, total 99.34. The empirical formula, based on 13 O apfu, is: Cu3.96Fe3+0.85Al0.19Ti0.03(V2.78As0.15Mo0.04)Σ2.97O13. Kainotropite is orthorhombic, Pnma, a = 14.139(2), b = 6.7102(7), c = 11.4177(15) Å, V = 1083.3(2) Å3, and Z = 4. The strongest reflections of the powder XRD pattern [d,Å(I)(hkl)] are: 8.89(100)(101), 5.728(33)(002), 3.698(35)(212), 3.357(52)(020,203), 3.034(77)(220), 2.968(60)(303), and 2.655(27)(321,204). The crystal structure was solved from single-crystal XRD data, R = 0.085. Kainotropite represents a novel structure type. Cu2+ polyhedra (distorted tetragonal pyramids and strongly distorted octahedra) and Fe3+ octahedra are connected via common edges to form zigzag ribbons. Adjacent ribbons are connected by both V2O7 and VO4 groups (isolated from each other) to form a heteropolyhedral pseudo-framework. The name kainotropite is derived from the Greek word καινóτρoπoς, unusual, in allusion to its uncommon (for natural vanadates) anionic composition: it is the first mineral containing both pyrovanadate (V2O7)4– and orthovanadate (VO4)3– anions.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.000 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.001 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".