A ocorrência de dumortierita na Serra do Espinhaço, Minas Gerais, Brasil, e sua comparação mineralógico-cristalográfica com outras variedades
Bibliographic record
Abstract
Samples of dumortierite from various localities of Brazil (Serra do Espinhaço-Minas Gerais, Macaúbas-Bahia) were analyzed with microprobe and the results were compared with those obtained from samples from Louvincourt dumortierite deposit (Quebec, Canada), Lincoln Hill-Champion Mines dumortierite deposit (Nevada, USA) Jack Creek dumortierite deposits (Montana), Acuélos (Chile) and from Madagascar (locality unknown). Infra-red spectroscopy (FTIR), ERP, Mössbauer effect spectroscopy (MS) were performed on the samples. Fourier transform infrared spectroscopy (FTIR), electron paramagnetic resonance (EPR) and Mössbauer spectroscopy have been used to study dumortierite samples of Brazil and of other origins. FTIRspectroscopy shows the existence of various environments for the OH-groups, which are related to substitutions and/or vacancies in the M1 octahedral site. Mössbauer spectroscopy consistently reveals the presence of divalent iron in 2 different octahedralsites, trivalent iron in one octahedral site and minor IVCT or IMMT iron. EPR also shows that isolated Fe3+ is present in various types of sites. The other signals ascribed to paramagnetic Fe3+ correspond to tetrahedral or more distorted octahedral sites.
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How this classification was reachedexpand
Full frame distilled prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. Learned from the 10,348 direct Codex labels and 10,348 direct Gemma labels. Candidate is the union of thresholded teacher heads; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels or direct frontier model labels.
Codex and Gemma teacher scores by category
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.002 | 0.000 |
| Meta-epidemiology (narrow) | 0.001 | 0.001 |
| Meta-epidemiology (broad) | 0.001 | 0.000 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.002 | 0.002 |
| Open science | 0.002 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.005 | 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 teacher head, 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".