| Borehole Number: |
| Prospecting Company: De Beers Holdings Botswana |
| Prospecting License No.: PL31/88 |
| Coordinates Type: WGS 84 |
| Coordinates Format: Decimal Degrees (DD) |
| Coordinates: -22.704422 , 27.883914 |
| 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 | Brown Topsoil. |
| 2. | 1 | 7 | Clay fraction is yellowish in colour. Weak calcretisation slightly silicified, highly weathered light brown coarsely textured kimberlite with inclusions of Amphiboliteibolite, quartz and k-feldspar 2m - overall brown/red staining. |
| 3. | 7 | 11 | Clay fraction is greenish in colur, 8m - 99% inclusions (qtz & pink kfs coated is greenish/yellow material) 10m-20% inclusions. |
| 4. | 11 | 18 | 20% inclusions. |
| 5. | 18 | 19 | Apple/olive, phlogopite bearing, olive poor coarsely textured, generally featureless hypabyssal kimberlite. Inclusions rich - variable proportions. |
| 6. | 19 | 20 | 95% inclusions (sheared greenish chloritic qtz, feldspar, kfs) |
| 7. | 20 | 21 | 100% inclusions (chloritised QF gneiss). |
| 8. | 21 | 29 | 80% inclusions ( pink kfs) |
| 9. | 29 | 30 | 40% inclusions |
| 10. | 30 | 39 | 30% inclusions (kfs, Amphiboliteibolite). |
| 11. | 39 | 44 | Below water table kimberlite is fresher, deeper olive green. Coarsely textured, featureless, phlogopite bearing, olivine poor, hypabyssal kimberlite macrocrystic phlog up to 3mm observed. 40% inclusions (kfs Amphiboliteibolite) |
| 12. | 44 | 47 | 40% inclusions (chlorite qtz, kfs, Amphiboliteibolite), |
| 13. | 47 | 48 | 30% inclusions (chlorite qtz, kfs, Amphiboliteib). |
| 14. | 48 | 49 | 70% inclusions. |
| 15. | 49 | 54 | 49m notable chloritisation of gneisses inclusions. |
| 16. | 54 | 59 | 90% inclusions (chloritic sheared qtz bearing rock + kfs). |
| 17. | 59 | 65 | 20% inclusions (chlorite qtz, kfs, Amphiboliteibolite), |
| 18. | 65 | 66 | 10% inclusions. |
| 19. | 66 | 67 | 5% inclusions. |
| 20. | 67 | 69 | 65m - distinct change to coloured inclusions fresh kimberlite. Olive green/grey featureless, coarsely textured hypabyssal kimberlite. |
| 21. | 69 | 71 | 5% inclusions 70m. |
| 22. | 71 | 77 | Basically inclusion fresh down to 90m. |
| 23. | 77 | 89 | Distinct lack of the usual coloured inclusions qtz, kfs. |
| 24. | 89 | 90 | Appears to be 100% grey, features hypabyssal kimberlite at first glance, but there is a high proportion of fine grained biotite Schist. Visually confusing and difficult to separate from kimberlite. |
| 25. | 90 | 94 | 94m predominantly Amphiboliteibolite 1x2mm phlog obs. |
| 26. | 94 | 95 | 50% inclusions (Amphiboliteibolite). |
| 27. | 95 | 96 | Mostly biotite Schist is some Amphiboliteibolite and pink gneiss. Phlogopite observed in fine drill product (could be bt). V isually confusing difficult to separate kimberlite. |
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