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 Borehole Number: 105/25/K003/1A/H5

 
 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: N/A
 End Drill: N/A
 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: N/A
 End of Hole (Depth): N/A
 Hole Diameter: N/A

 
 Log Formation:
No.From (m)To (m) Log Formation
1.0 1Topsoil
2.1 2Topsoil with quartz and febric basement rubble.
3.2 4Basement rubble, silicified kimberlite (1%), clay 1%.
4.4 5Basement rubble no kimberlite evident.
5.5 950% green kimberlitic clay, 50% basement rubble, no kimberlite clay, dominant quartzite rubble.
6.9 15Quartzite, Amphiboliteibolite, pink feldspar gneiss rubble set in a gritty matrix.
7.15 18Basement rich rubble but green clay (kimberlitic) coats grains.
8.18 2090% kimberlitic clay, 10% quartzite.
9.20 2220% kimberlitic clay, 80% blue Schist, pink gneiss and quartzite.
10.22 2470% inclusions set in green kimberlitic clay.
11.24 2690% inclusions.
12.26 2830% inclusions in kimberlite clay.
13.28 30Blue clay with numerous phlogopites.
14.30 34Blue kimberlite, pitted where inclusions have become free. Kimb 60%, inclusions 40%, no clay.
15.34 45Blue kimberlite with varying inclusions of 30% - 70% phlogopites visible.
16.45 65Varying proportions of Amphiboliteibolite, quartz - feldspathic gneiss and quartzite. Propably represents xenolithic material as many chips show blue clay coatings.
17.65 813% kimberlite, 97% Amphiboliteibolite, felsite gneiss.
18.81 8250% blue kimberlite, 30% felsite, 20% Amphiboliteibolite.
19.82 8420% kimberlite, 80% inclusions.
20.84 8550% Amphiboliteibolite, 50% kimberlite.
21.85 8770% kimberlite, numerous phlogopites, 30% quartzite.
22.87 9098% kimberlite blue aphanitic and uniform with no vissible olivine macrocrysts, some phlogopites up to 5mm large.
23.90 9299% kimberlite.
24.92 9580% kimberlite, 20% inclusions.
25.95 101Kimberlite to 102m varies from 90% to 30% generally becoming less abundant down hole.
26.101 10590% Amphiboliteibolite 10% quartzite.
27.105 107Blue clay coating to chips.
28.107 108Serpentine visible.
29.108 110Lithology 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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