PYRACMONITE, (NH4)3Fe(SO4)3, A NEW AMMONIUM IRON SULFATE FROM LA FOSSA CRATER, VULCANO, AEOLIAN ISLANDS, ITALY
Why this work is in the frame
A frame that forgets how it found something cannot be audited. These are the routes that admitted this work.
Bibliographic record
Abstract
The new mineral species pyracmonite , ideally (NH 4 ) 3 Fe(SO 4 ) 3 , was found in a medium-temperature (~250°C) active intracrater fumarole at La Fossa crater, Vulcano, Aeolian Islands, Sicily, Italy. It occurs on a pyroclastic breccia as colorless to white prismatic crystals up to 0.2 mm in length, in association with salammoniac and kremersite. The mineral is trigonal, space group R 3 c (no. 161) with a 15.2171(14), c 8.9323(8) A, V 1791.3(3) A 3 and Z = 6. The strongest six reflections in the X-ray powder-diffraction pattern [ d obs in A( I )( hkl )] are: 7.596(100)(110), 3.320(30)(122), 3.371(26)(131), 4.358(23)(121), 2.829(14) (312), and 2.863(8)(321). The empirical formula, based on 12 anions, is [(NH 4 ) 2.74 K 0.23 ] ∑2.97 (Fe 0.94 Al 0.04 ) ∑0.98 S 3.02 O 12 , and the simplified formula (NH 4 ,K) 3 (Fe,Al)(SO 4 ) 3 . The measured density is 2.22(1) g/cm 3 , and D calc is 2.228 g/cm 3 . The mineral is uniaxial, and the average index of refraction index is 1.562(3) (λ= 589 nm). Using single-crystal X-ray-diffraction data, the structure was refined to a final R ( F ) = 0.039 for 1010 independent observed reflections [ I > 2σ( I) ]. The mineral is identical to the synthetic compound (NH 4 ) 3 Fe(SO 4 ) 3 and is isostructural to the high-temperature phase of the synthetic compound (NH 4 ) 3 In(SO 4 ) 3 . Building blocks of the structure are (Fe,Al)O 6 octahedra and SO 4 tetrahedra, which are linked together to form infinite columns [(Fe,Al)(SO 4 ) 3 ] ∞ along [001]. The two independent (Fe,Al)–O distances are 1.959(1) and 1.998(1) A; in the sulfate anion, the S–O distances range from 1.415(2) to 1.485(1) A. The ammonium ions, only partly replaced by K + ions, interact with the oxygen atoms of the sulfate groups via hydrogen bonds.
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.
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 | 0.001 | 0.000 |
| Meta-epidemiology (narrow) | 0.000 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.000 | 0.000 |
| Science and technology studies | 0.001 | 0.001 |
| Scholarly communication | 0.001 | 0.000 |
| Open science | 0.001 | 0.000 |
| Research integrity | 0.000 | 0.001 |
| Insufficient payload (model declined to judge) | 0.003 | 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 it