STRATA
Borehole correlation
When two cores share the same mineral across consecutive beds at the same depth, a seam runs between them, like one rock layer traced across neighbouring boreholes. Enter your token to find every core your seam reaches.
Reading all 10,000 seeds…
Collection records
Counted across all 49,995,000 pairs. Each tier means at least that many beds in a row, so every core has at least 3 Seam partners and no two cores match all 8 beds. Between any two cores, only the longest run counts.
| Tier | Rule | Pairs | Cores with one |
|---|---|---|---|
| Seam | 3+ beds in a row | 69,664 | 10,000 |
| Deep seam | 4+ beds in a row | 3,593 | 5,141 |
| Mother lode | 5+ beds in a row | 167 | 330 |
| Rare vein | 6+ beds in a row | 7 | 14 |
| Twin cores | 7 beds in a row | 1 | 2 |
Two boreholes, 375 tokens apart, hit the same seven layers of rock before splitting at the very bottom. #2119 and #2494 are the only twin cores in the collection.