And this was a follow up announcement - lol.
FOUR HUNDRED AND SEVEN MACRO AND MICRO DIAMONDS RECOVERED FROM 258 KG
OF SAMPLES COLLECTED FROM BEHRADIH KIMBERLITE, THE VAST MAJORITY OF
WHICH ARE CLEAR, COLOURLESS STONES.
The Chhattisgarh joint venture partners ("Oropa Limited and
B.Vijaykumar Technical Services Pvt Ltd") recently completed a fine
diamond and mineralogical sampling programme comprising the
collection and analysis of eight weathered surface samples with a
combined weight of 258 kg from various points located within the
Behradih kimberlite as illustrated on Figure 1 in the attached
Appendix "A". The samples, (BSS#01-08) were airfreighted to Perth in
August for screening and detailed analyses. Detailed individual
sample results from these eight samples are tabulated in Table 1 in
Appendix "A". It should be noted that all eight samples contained
diamonds and abundant indicator minerals. Detailed petrographic
analysis of fresher kimberlite obtained from sub-surface sampling
will be necessary to more precisely evaluate the nature and
variability of the kimberlite diatreme.
A total of 497 micro and macro (-0.4mm) diamonds have now been
recovered from the nine weathered Behradih kimberlite samples,
including the original sample collected in July. Results of screening
analysis through square mesh screens are tabulated below;
BEHRADIH SURFACE KIMBERLITE SAMPLE DIAMOND SIZE DISTRIBUTION
MESH SIZE 0.1 0.15 0.21 0.30 0.43 0.60 0.85 1.18
mm mm mm mm mm mm mm mm
Diamonds 262 141 55 28 5 3 2 1
Recovered
The recovered diamonds have been subjected to size distribution
analysis using Rombouts sampling and statistical evaluation of
diamond deposits methods (L. Rombouts, Journal of Geochemical
Exploration 53-1995). Figure 1 in Appendix "A" extrapolates the
plotted diamonds' as Cumulative Carats per hundred tonnes versus Size
and indicates that grade and size may be significant. Statistical
analysis of the size distribution also suggests that diamonds
exceeding 1 carat in size are probable in this kimberlite.
Analysis of the diamond populations observed within the fine diamonds
is also encouraging. The data suggests a large proportion of good
shapes and clear, white stones. As per the majority of kimberlite
diamond populations, resorption features are apparent, although the
overall degree of resorption does not appear to be dominant as is
the case with kimberlites containing a high proportion of low value
diamonds. Further evaluation of the stone characteristics is
currently in progress.
Although it is not possible to make precise deductions regarding
grade and size distribution from the 318 kg of surface kimberlite
material collected to date, it is clear that the Behradih pipe has
fine diamond counts and, most significantly, yields macro-diamonds
from very small sample sizes. Analysis of the pyrope garnets and
chrome spinels recovered from the Behradih samples as produced in the
accompanying Figures 3, 4 and 5 also provide supporting evidence that
the Behradih kimberlite sampled source material within the diamond
stability field and is diamond bearing. Available micro-diamond andmineralogic
al data points to the presence of measurable grade.
The Behradih kimberlite is located on the western side of the Raipur
kimberlite pipe cluster and it is accessed from the main interstate
highway passing through the block. In the mid-1990's the Directorate
of Geology and Mines ("DGM") completed a diamond coring programme
comprising five holes for a total of 708 metres (one vertical hole
and four angled holes), which indicated that the Behradih kimberlite
persists to a minimum of 180 metres. This drill pad is located in the
central portion of the kimberlite and is marked on the accompanying
map. However, the coring programme did not establish whether the pipe
was single or multi phased (more than one kimberlite body contained
within the one diatreme). The Behradih kimberlite has a surface area
of approximately 3.2 ha, as determined by the DGM. The joint venture
partners are nearing agreement with their negotiations with the DGM
to purchase these five cores for preliminary studies. If successful,
the cores will be airfreighted to Australia and Republic of South
Africa ("RSA") for detailed mineralogy evaluation.
The Chhattisgarh joint venture partners are currently awaiting
approval from the Government of India's Forestry Department to
undertake comprehensive, large scale kimberlite evaluation
programmes, including drilling, trenching and bulk sampling.
Preliminary marking out of the surface of the Behradih kimberlite has
recently commenced for gridding and clearing to permit drilling and
surface excavation. An Indian fabrication contractor has been awarded
the contract to construct a Plietz jig with a nominal capacity of 10
tonnes per day, which will initially be used to bulk sample
kimberlite until the design of a more sophisticated Dense Media
Separation ("DMS") plant is finalized. The Plietz jig will enable the
joint venture partners to obtain more detailed information about
Behradih and the other pipes.
The joint venture's nearby Mainpur laboratory facility is now
operational and approximately 150 samples have been processed over a
recently installed Wilfley table and subjected to TBE separation
since the resumption of this field season's exploration programmes.
These concentrates were delivered to the local laboratories earlier
this week. A further 500+ regional steam sediment and loam samples
have been collected and are awaiting treatment in Mainpur before
being sent to Johannesburg, RSA. A number of the samples collected
this season are follow-up stream sediment samples obtained from
priority targets generated from the initial orientation sampling
programme.
The expedited processing and analytical methods currently being
employed by the joint venture partners are designed to more rapidly
trace the high interest indicator mineral dispersion trails to their
possible kimberlitic sources. During the coming months, known and
newly discovered kimberlites will be treated through the Plietz jig
to more accurately evaluate their potential. This data will be
collated and used for the final design criteria of the DMS plant.
The fine diamond and heavy mineral results obtained to date for
Behradih are extremely encouraging, although it should be noted that
the overall combined sample sizes are relatively small. Additional
work will be conducted during the current field season at Behradih
and other locations in the Raipur kimberlite field to more accurately
determine their prospectivity and economic potential.
The acquisition of drilling and bulk sampling equipment is high on
the joint venture partners' priority list to advance the project as
expeditiously as possible throughout the remainder of this field
season (+/-7 months). Detailed kimberlite evaluation programmes
combined with the regional airborne geophysical survey, regional
stream and loam sampling programme, on-site sample processing and
ground geophysical surveys to delineate new kimberlite sources will
ensure that rapid progress with the exploration and development of
the highly prospective cratonic D-7 block will be accomplished before
the end of the current season.
P C Christie
MANAGING DIRECTOR
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