Bibliographic record
Abstract
Abstract The 23-year evaluation history of the Diavik kimberlites (1994–2017) commenced with elevated microdiamond stone counts from small samples of drill core. These stone counts equated with high sample grades, grades that were higher than anyone had expected (2–5 carats per tonne [ct/t]), and caused many experienced explorers to change their opinions on the prospectivity of small kimberlites (1–2 ha in surface area). The diamond size-frequency distributions were coarser trending, and the diamond quality was “mixed,” resulting in >1-mm diamond prices of about US$100 per ct, slightly better than the world average. This grade and price combination gave ore values ranging from US$200 to US$500 per tonne and, with four kimberlites, the Diavik joint venture partners estimated that there would be sufficient ore to underpin a 20-year mine life at a treatment rate of 2.2 million tonnes per annum. Primary diamond deposits are usually sampled on 50- or 100-m grids. Grade drilling at Diavik was conducted on 25-m centers, allowing for 12- × 6-in holes in each kimberlite. The kimberlites are located beneath Lac de Gras and had to be bulk sampled underground to generate diamond parcels (approximately 12,000 and 8,000 ct) for sorting and valuation. Three of the kimberlites transitioned from open-pit to underground mines (two sublevel retreats and one cut and fill). The fourth kimberlite narrows at depth and is unlikely to be mined from underground. Grade reconciliation has presented challenges; each kimberlite comprises three to four geologic units and plant feed can comprise ore from three kimberlites concurrently. Careful ore management and tracking has overcome these difficulties, meaning that grade, size-frequency, and size-quality reconciliations have been meaningful and, for the most part, have varied less than ±5% on an annual basis. The Diavik mine is neither the largest nor the smallest deposit in the world. However, by the end of its life it will have produced about 7 million carats of diamonds per annum for 22 years at an average grade of 3.4 ct/t. It represents an exceptional diamond resource for kimberlites ~100 m in diameter, considering that it is also located in one of the coldest and remotest locations on Earth.
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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 | 0.000 | 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 | 0.000 | 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 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".