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Exploration Borehole


	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

Brown Topsoil.

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.

Clay fraction is greenish in colur, 8m - 99% inclusions (qtz & pink kfs coated is greenish/yellow material) 10m-20% inclusions.

20% inclusions.

Apple/olive, phlogopite bearing, olive poor coarsely textured, generally featureless hypabyssal kimberlite. Inclusions rich - variable proportions.

95% inclusions (sheared greenish chloritic qtz, feldspar, kfs)

100% inclusions (chloritised QF gneiss).

80% inclusions ( pink kfs)

40% inclusions

10.

30% inclusions (kfs, Amphiboliteibolite).

11.

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.

40% inclusions (chlorite qtz, kfs, Amphiboliteibolite),

13.

30% inclusions (chlorite qtz, kfs, Amphiboliteib).

14.

70% inclusions.

15.

49m notable chloritisation of gneisses inclusions.

16.

90% inclusions (chloritic sheared qtz bearing rock + kfs).

17.

20% inclusions (chlorite qtz, kfs, Amphiboliteibolite),

18.

10% inclusions.

19.

5% inclusions.

20.

65m - distinct change to coloured inclusions fresh kimberlite. Olive green/grey featureless, coarsely textured hypabyssal kimberlite.

21.

5% inclusions 70m.

22.

Basically inclusion fresh down to 90m.

23.

Distinct lack of the usual coloured inclusions qtz, kfs.

24.

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.

94m predominantly Amphiboliteibolite 1x2mm phlog obs.

26.

50% inclusions (Amphiboliteibolite).

27.

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.