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 Borehole Number: 105/25/K003/1A/H4

 
 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: 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 1Brown Topsoil.
2.1 7Clay 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 11Clay fraction is greenish in colur, 8m - 99% inclusions (qtz & pink kfs coated is greenish/yellow material) 10m-20% inclusions.
4.11 1820% inclusions.
5.18 19Apple/olive, phlogopite bearing, olive poor coarsely textured, generally featureless hypabyssal kimberlite. Inclusions rich - variable proportions.
6.19 2095% inclusions (sheared greenish chloritic qtz, feldspar, kfs)
7.20 21100% inclusions (chloritised QF gneiss).
8.21 2980% inclusions ( pink kfs)
9.29 3040% inclusions
10.30 3930% inclusions (kfs, Amphiboliteibolite).
11.39 44Below 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 4740% inclusions (chlorite qtz, kfs, Amphiboliteibolite),
13.47 4830% inclusions (chlorite qtz, kfs, Amphiboliteib).
14.48 4970% inclusions.
15.49 5449m notable chloritisation of gneisses inclusions.
16.54 5990% inclusions (chloritic sheared qtz bearing rock + kfs).
17.59 6520% inclusions (chlorite qtz, kfs, Amphiboliteibolite),
18.65 6610% inclusions.
19.66 675% inclusions.
20.67 6965m - distinct change to coloured inclusions fresh kimberlite. Olive green/grey featureless, coarsely textured hypabyssal kimberlite.
21.69 715% inclusions 70m.
22.71 77Basically inclusion fresh down to 90m.
23.77 89Distinct lack of the usual coloured inclusions qtz, kfs.
24.89 90Appears 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 9494m predominantly Amphiboliteibolite 1x2mm phlog obs.
26.94 9550% inclusions (Amphiboliteibolite).
27.95 96Mostly 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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