| Borehole Number: |
| Prospecting Company: De Beers Holdings Botswana |
| Prospecting License No.: PL31/88 |
| Coordinates Type: WGS 84 |
| Coordinates Format: Decimal Degrees (DD) |
| Coordinates: -22.7037 , 27.883476 |
| Location: Lerala |
| Start Drill: 0000-00-00 |
| End Drill: 0000-00-00 |
| Borehole Type: Exploration |
| Drilling Method: Core |
| Sample Type: Core |
| Depth of Surface Casing: N/A |
| Azimuth: Degrees |
| Hole Inclination: N/A |
| Collar Elevation: N/A |
| Borehole Water Strike: Metres |
| End of Hole (Depth): N/A |
| Hole Diameter: Millimetres |
| Log Formation: |
| No. | From (m) | To (m) | Log Formation |
|---|
| 1. | 0 | 1 | Topsoil |
| 2. | 1 | 2 | Topsoil with quartz and febric basement rubble. |
| 3. | 2 | 4 | Basement rubble, silicified kimberlite (1%), clay 1%. |
| 4. | 4 | 5 | Basement rubble no kimberlite evident. |
| 5. | 5 | 9 | 50% green kimberlitic clay, 50% basement rubble, no kimberlite clay, dominant quartzite rubble. |
| 6. | 9 | 15 | Quartzite, Amphiboliteibolite, pink feldspar gneiss rubble set in a gritty matrix. |
| 7. | 15 | 18 | Basement rich rubble but green clay (kimberlitic) coats grains. |
| 8. | 18 | 20 | 90% kimberlitic clay, 10% quartzite. |
| 9. | 20 | 22 | 20% kimberlitic clay, 80% blue Schist, pink gneiss and quartzite. |
| 10. | 22 | 24 | 70% inclusions set in green kimberlitic clay. |
| 11. | 24 | 26 | 90% inclusions. |
| 12. | 26 | 28 | 30% inclusions in kimberlite clay. |
| 13. | 28 | 30 | Blue clay with numerous phlogopites. |
| 14. | 30 | 34 | Blue kimberlite, pitted where inclusions have become free. Kimb 60%, inclusions 40%, no clay. |
| 15. | 34 | 45 | Blue kimberlite with varying inclusions of 30% - 70% phlogopites visible. |
| 16. | 45 | 65 | Varying proportions of Amphiboliteibolite, quartz - feldspathic gneiss and quartzite. Propably represents xenolithic material as many chips show blue clay coatings. |
| 17. | 65 | 81 | 3% kimberlite, 97% Amphiboliteibolite, felsite gneiss. |
| 18. | 81 | 82 | 50% blue kimberlite, 30% felsite, 20% Amphiboliteibolite. |
| 19. | 82 | 84 | 20% kimberlite, 80% inclusions. |
| 20. | 84 | 85 | 50% Amphiboliteibolite, 50% kimberlite. |
| 21. | 85 | 87 | 70% kimberlite, numerous phlogopites, 30% quartzite. |
| 22. | 87 | 90 | 98% kimberlite blue aphanitic and uniform with no vissible olivine macrocrysts, some phlogopites up to 5mm large. |
| 23. | 90 | 92 | 99% kimberlite. |
| 24. | 92 | 95 | 80% kimberlite, 20% inclusions. |
| 25. | 95 | 101 | Kimberlite to 102m varies from 90% to 30% generally becoming less abundant down hole. |
| 26. | 101 | 105 | 90% Amphiboliteibolite 10% quartzite. |
| 27. | 105 | 107 | Blue clay coating to chips. |
| 28. | 107 | 108 | Serpentine visible. |
| 29. | 108 | 110 | Lithology to bottom of the seems to be a dominant quartzite - feldspartic gneiss although some 2% g blue kimberlite at 110m is evedent. |
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