JOHNSENITE-(Ce): A NEW MEMBER OF THE EUDIALYTE GROUP FROM MONT SAINT-HILAIRE, QUEBEC, CANADA
Bibliographic record
Abstract
La johnsenite-(Ce), de composition ideale Na 12 (Ce,La,Sr,Ca,□) 3 Ca 6 Mn 3 Zr 3 W (Si 25 O 73 ) (CO 3 )(OH,Cl) 2 , est un nouveau membre du groupe de l'eudyalite, decouvert au mont Saint-Hilaire, Quebec; il s'agit de l'analogue tungstenifere de la zirsilite-(Ce). Elle se presente en cristaux squelettiques fortement corrodes atteignant 4 mm, et 1 cm en aggregats. Lui sont associes albite, calcite, pectolite, aegyrine, fluorapophyllite, zirsilite-(Ce), un mineral du groupe de la burbankite, dawsonite, rhodochrosite, epididymite, galene, molybdenite, pyrite, pyrrhotite, quartz, une amphibole, sphalerite, stillwellite-(Ce), titanite, cerite-(Ce), tuperssuatsiaite, steacyite, catapleiite, zakharovite, natrolite et microcline. Elle est transparente a translucide, avec un eclat vitreux et une rayure blanche. Elle est cassante, avec une durete de Mohs de 5 a 6. Il n'y a aucun clivage ou plan de separation visible, et la fracture est inegale. Le mineral est uniaxe negatif, avec ω 1.648(1) et e 1.637(1). Sa symetrie est trigonale, groupe d'espace R3m, a 14.237(3) et c 30.03(1) A, V 5271(2) A 3 , Z = 3. Les huit raies les plus intenses du spectre de diffraction X (methode des poudres) [d en A (I)(hkl)] sont: 11,308(95)(101), 9.460(81)(012), 4.295(34)(205), 3.547(36)(220), 3.395(38)(131), 3.167(75)(217), 2.968(100)(315) et 2.849(81)(404). Nous presentons le spectre infrarouge de la johnsenite-(Ce). Les resultats de huit analyses a la microsonde electronique, dont trois sur le cristal ayant servi a l'ebauche de la structure, ont donne, en moyenne, Na 2 O 10.47, K 2 O 0.25, CaO 8.98, SrO 1.60 MnO 5.43, FeO 1.61, Y 2 O 3 0.70, La 2 O 3 1.56, Ce 2 O 3 3.01, Pr 2 O 3 1.14, Nd 2 O 3 0.89. Sm 2 O 3 0.12, Gd 2 O 3 0.33, Dy 2 O 3 0.14. TiO 2 0.73, ZrO 2 9.60, HfO 2 0.04, Nb 2 O 5 0.82, WO 3 5.23, SiO 2 43.16, Cl 0.77, CO 2 (1.27), H 2 O (0.32), O = Cl -0.17, pour un total de 97.99% (poids). La concentration de CO 2 et celle de H 2 O ont ete calculees selon la stoechiometrie etablie a partir de l'analyse de la structure. La formule empirique de la johnsenite-(Ce), fondee sur 29 atomes de (Si 4+ , Zr 4+ , Ti 4+ , Hf 4+ , Nb 5+ , W 6+ ) et un groupe (CO 3 ), selon les resultats de l'analyse structurale, est: Na 11.74 ([Ce 0.64 La 0.33 Dy 0.03 ]Σ 1.00 Sr 0.54 Ca 0.51 Y 0.22 K 0.19 ) Σ2.46 (Ca 5.06 [Pr 0.24 Nd 0.18 Gd 0.06 Sm 0.02 ]Σ 0.50 Mn 0.44 )Σ 0 (Mn 2.22 Fe 0.78 ) Σ3 (Zr 2.71 Ti 0.32 Hf 0.01 ) Σ3.04 (W 0.78 Nb 0.21 ) Σ0.99 Si 24.97 O 73 (CO 3 ) (OH,Cl 0.75 ) Σ2 , D meas . = 3.24(3) g/cm 3 ; D calc . = 3.23 g/cm 3 . La structure est faite de quatre couches, qui definissent une polarite, telle qu'indiquee par une analyse statistique des intensites des pics de diffraction, la composition des couches et le potentiel electrostatique des monocristaux. Le nom du mineral honore Ole Johnsen, du Musee Geologique, Universite de Copenhague, au Danemark.
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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 | 0.002 | 0.002 |
| Science and technology studies | 0.004 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.001 |
| Research integrity | 0.001 | 0.000 |
| Insufficient payload (model declined to judge) | 0.007 | 0.001 |
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".