| Wed 26 Jul 2006, 8:00 | | Diamond Core - Moving the De Kalk alluvial diamond |
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DMR
DMR
Diamond Core - Moving the De Kalk alluvial diamond project up the value
chain - delineation of a channElised
12Mt gravel deposit
DIAMOND CORE RESOURCES LIMITED
(Incorporated in the Republic of South Africa)
(Registration number 1998/013468/06)
Share code: DMR & ISIN Number: ZAE000076956
("Diamond Core" or "the company")
Moving the De Kalk alluvial diamond project up the value chain - delineation of
a channElised
12Mt gravel deposit
Venmyn Rand (Pty) Ltd ("Venmyn") was commissioned by the directors of Diamond
Core Resources Limited ("Diamond Core") to prepare an independent update of the
De Kalk section of the Samadi/Diamond Core Competent Persons Report, prepared in
June 2005, to incorporate the results of the subsequent exploration programme.
The findings of the review have been used to compile this announcement to inform
shareholders of the advancements that have taken place since 2005.
The De Kalk project is held in a 50:50 joint venture in Samadi (Douglas)
Exploration (Pty) Limited with Sefalana Resources (Pty) Limited, a broad based
black empowerment consortium headed by Mr Lesedi Rakgokong, as per the terms of
an Agreement more fully described in the Circular to shareholders dated 3rd
February 2006.
A comprehensive report on the results of the first phase exploration carried out
on the De Kalk project, as well as the full CPR, both compiled by Venmyn, are
available on the Company website at www.diamondcore.co.za.
Commenting on the result, Theo Botoulas, CEO of Diamond Core, said "The extent
and tonnages of the alluvial gravels proved up at De Kalk, fall well within the
minimum tonnage of 5 million tonnes for Diamond Core to continue with the
exploration of the deposit, and the next step in the process is to determine the
grade of the deposit, by conducting a bulk sampling programme. The grade will be
determined by treating up to 1 million tonnes (
15% of the estimated gravel
tonnage) of the alluvial gravel, which will further move the project up the
value chain."
"The channelised nature of the deposit provides potential for trap sites. There
is potential for the addition of further gravel tonnages to this estimate as the
terrace remains open to the north for further drilling and gravel delineation.
The gravels lack banded ironstones and excessive calcretisation, which makes the
De Kalk deposit an important project in the Diamond Core portfolio. Using the
geological model created from the drilling results, the Company will site the
exploration trenches and bulk sampling infrastructure in order to optimise the
sampling operations."
The De Kalk alluvial diamond project is located on the farm De Kalk 37, situated
on the southern bank of the Orange River, in the Hopetown district of the
Northern Cape Province, South Africa. The gravel deposits in the project area
were previously mined by three separate companies at various stages. To date,
total recorded production from the farm is estimated at 644cts. No information
with respect to the actual tonnes mined and, therefore the grade, is available.
Prior to the CPR being released, Samadi had carried out a preliminary geological
mapping exercise on the project. No drilling had been conducted. Since then,
two drilling programmes, totalling 368 boreholes, have been undertaken. These
boreholes were logged largely by Robert Cooke Mineral Consultants ("RCMC"), a
geological consulting company. RCMC also carried out a modelling exercise using
the information from the drilling programmes. It is the information from these
two drilling programmes that was used to update the information previously
disclosed in the CPR.
The Phase 1 drilling programme was carried out to broadly outline the areas
underlain by gravel deposits. The Phase 2 infill drilling programme was carried
out to provide detailed drilling information, for geological modelling of the
gravel deposit to take place. The details of these two drilling programs are
outlined in the table below:-
PHASE 1 PHASE 2
Objective Reconnaissance Detailed Drilling
Drilling
No of boreholes drilled 118 250
Acronym given to borehole DK D
numbers
Date of drilling 26 Jan 2006 - 15 20 April 2006 - 11
programme Feb 2006 May 2006
Type of drilling Rotary Air Blast Reverse
Circulation
Name of drilling company Muller Bore DP Grobler
Boordienste
Borehole spacing 100m x 1,000m 100m x 200m
Total meters drilled 724m 1,912m
Average depth of 6.1m 7.6m
boreholes
Name of borehole logger RCMC RCMC
No. of boreholes used in 35 246
gravel modelling
No. of boreholes not used 83 4
in gravel modelling
The drilling programmes identified four gravel horizons on De Kalk, namely, from
the base of the sequence:-
- a Basal A gravel deposit, which occurs immediately above the bedrock
formation;
- a Basal B gravel deposit, which either occurs immediately above the Basal A
deposit, or above the bedrock but has a sand layer separating it from the
bedrock;
- a Suspended gravel, which occurs near surface in between overburden sandy
layers; and
- a poorly developed Rooikoppie gravel that occurs as a surface deflation
deposit on portions of the project area. This gravel, and other near surface
gravels, had been the focus of the previous mining activities.
The Basal A gravels, Basal B gravels and Suspended Gravels were modeled by RCMC
using the computer software programme, Surfer(R) 8. Contour maps were produced
illustrating the thickness of the individual gravel packages, the overburden
thickness of each gravel, as well as the estimated stripping ratio of the
gravels. Venmyn also carried out a similar modelling exercise using the same
database used by RCMC, in order to verify the gravel tonnages calculated by
RCMC.
It should be noted that the specific gravity ("SG ") for the gravel packages,
has not been established via scientific methods, but rather been approximated
from experience that RCMC has had with alluvial gravel deposits of a similar
nature. Once a bulk sample has been taken, the SG"s will be verified using
scientific methods.
Both RCMC and Venmyn modelled the gravel deposits, which allowed for the
independent calculation of gravel volumes contained in each of the three
horizons. When the estimated SG of the gravels was factored in, a tonnage of
between 10.9Mt (RCMC) and 12.1Mt (Venmyn) was calculated for De Kalk.
Both Venmyn and RCMC only modelled the gravels in the areas where drilling had
taken place. It is expected that the gravels extend northwards, beyond the
limit of the current drilling.
Gravel deposits of a similar nature are being mined adjacent to the project as
well as in the general locality. RCMC are familiar with the mining in the area
and report that these deposits generally carry grades of between 0.3cpht and
0.8cpht for the Basal gravels and 0.1cpht and 0.3cpht for the Suspended gravels.
It can be assumed the gravels at De Kalk could carry similar grades. It must be
stressed, however, that these grades are only assumed and have not been verified
by bulk sampling or trial mining, which is expected to take place during the
next phase of exploration on the project.
Once the bulk sampling exercise has been completed, it will be possible to
estimate the grade of the deposit with some confidence. Only after this
exercise, and the sale of a parcel of diamonds into today"s market, can the
gravel deposit at De Kalk be classified as an Inferred Diamond Resource.
Since November 2005, when the new order Prospecting Right was granted for De
Kalk, it has been the focus of exploration by Diamond Core.
Proving up the exploration project from preliminary exploration results and
moving it into the Inferred Diamond Resource category may increase its value,
providing that the grades and diamond values established indicate an
economically viable project. It should be noted that diamond mining is being
conducted on the adjacent property to the south of De Kalk which has been
producing diamonds sustainably over the last two years.
For more information on Diamond Core Resources Ltd, please visit our website on
www.diamondcore.co.za.
This SENS announcement was independently prepared by Venmyn Rand (Pty) Ltd on
the 25th July 2006.
26th July 2006
Epsom Downs
Sandton
Sponsor
River Group
Date: 26/07/2006 08:00:30 AM Produced by the JSE SENS Department
