A BOND-VALENCE APPROACH TO THE STRUCTURE, CHEMISTRY AND PARAGENESIS OF HYDROXY-HYDRATED OXYSALT MINERALS. III. PARAGENESIS OF BORATE MINERALS
Bibliographic record
Abstract
A connection is established between the crystal structures of borate minerals and the conditions (pH, log[H 2 O]) at which they are stable, using the approach developed by Schindler & Hawthorne (2001a, b). Structural units in borate minerals may be formally related by two types of chemical reactions, one of which consumes H and the other that consumes (H 2 O). Combining these equations with the law of mass action, an expression for pH can be formulated that allows arrangement of the structural units in pH–log[H 2 O] space and calculation of the slopes of the associated phase-boundaries. The result is a pH–log[H 2 O] activity–activity diagram with the correct topology and a relative scale along each of the axes. Structural units from minerals of similar paragenesis occur in contiguous fields of this activity–activity diagram. The general classes of polymerization of borate groups in the structural units change systematically across this activity–activity diagram. With increasing activity of (H 2 O), structural units trend from frameworks → sheets → chains → clusters → isolated polyhedra. The proportion of tetrahedrally coordinated B ( [4] B × 100/{ [3] B + [4] B}) in the structural units increases with increasing pH across the activity–activity diagram; this relation combines with the valence-matching principle to indicate that interstitial species of higher acidity ( e.g. , Ca, Mg) form minerals at higher pH than interstitial species of lower acidity ( e.g. , Na, K). The average basicity of borate clusters in aqueous solution is a linear function of the pH of that solution at the maximum concentrations of each of the clusters (Hawthorne et al. 1996). The proportion of [4] B and the average basicity of all clusters in aqueous borate solutions are smooth functions of the pH of the solution; moreover, the average basicity of the clusters (dissolved species) is a linear function of the proportion of [4] B in solution.
Fetched live from OpenAlex and de-inverted. Abstracts are not stored in this database: the inverted indexes are 8.6 GB of the frame’s 9.3 GB of text, and the host has 13 GB free.
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) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.001 |
| Bibliometrics | 0.001 | 0.001 |
| Science and technology studies | 0.001 | 0.002 |
| Scholarly communication | 0.001 | 0.002 |
| Open science | 0.002 | 0.001 |
| Research integrity | 0.001 | 0.001 |
| Insufficient payload (model declined to judge) | 0.006 | 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".