system of mathematical calculation of a kimberlite diamond grade
DESCRIPTION
Diamond grade is the most important parameter of a kimberlite rock. A few hundreds of microprobe analyses of garnets picked randomly from a kimberlite concentrate might be enough to calculate mathematically accurate diamond grade.TRANSCRIPT
PrefaceThose who found kimberlite but not sure about its real value, needs to have at least
three major parameters: the size of kimberlite, its diamond grade and the cost of its
one carat of diamonds. Among them the diamond grade is the most important one.
Among thousands of kimberlites known over the world there are very few of them
became a profitable diamond mine.
Delineation drilling will provide answer for the first question, gemologist will apprise
the value of one carat of diamonds, but nobody can give accurate figure of a
kimberlite diamond grade before the start of mining.
The last decade investigations show that the kimberlite diamond grade can be
successfully calculated mathematically based on chemistry of garnets picked
randomly from a HMC of kimberlite.
System of MathematicalCalculations of
a Kimberlite Diamond Grade
Igor Kryvoshlyk, [email protected] 416-248-8514
Igor Kryvoshlyk joined SouthernEra Resources Limited in May 1995 as a mineralogist… During…more than 10 year period with SouthernEra, Igor spent most of his time doing microscope examination…His sorting of various kimberlitic minerals was always meticulously done, despite this being a painstaking task…
Igor is the only person I have known in all my years of kimberlite exploration, who is able to distinguish, with a high degree of certainty, optically and before probe analysis, between kimberlitic and non kimberlitic chromites and ilmenites. Similarly, he has an uncanny ability to distinguish eclogitic garnets from other, similar coloured garnets…
During his stay with us, Igor spent a lot of time collecting data for a huge database of kimberlitic mineral electron probe analyses. He spent a lot of time building research models from this data for the prediction of the location of kimberlites and predicting economic viability and even prediction of the grade of kimberlites from his mineral database…
Igor has a lively and enquiring mind and I had many interesting discussions with him, where he was often prepared to buck conventional wisdom and propose new and sometimes radical ideas. An attribute I greatly admire…
Dr. Christopher Mark Hubert Jennings.Chairman and former President and CEO SouthernEra Diamonds. January 4, 2006.
About the Author
Brief History of Research
• 1995. Senior mineralogist for SouthernEra Diamonds, Toronto, Canada.
Beginning of research. DO-27 kimberlite (NWT, Canada) diamond grade
was calculated as 1 cpht [by Peregrine Diamonds using standard method]
• 2000. First test of the new System. DO-27 diamond grade calculated
around 70 cpht [based on 58 garnet grains and 1 week of work]
• 2005. Re-evaluation (why?) of DO-27 by Peregrine Diamonds - Intensive
drilling and sampling. New grade is around 80 cpht [by standard method
and months / years of work]
DO-27 Diamond grade
“Kennecott Canada Exploration Inc. processed over
1,200 tonnes of diatreme kimberlite, (the Tli Kwi Cho
kimberlite pipe) coming up with a meagre diamond
grade of 0.01 carat per tonne” (or 1 cpht).
by Will Purcell 2004-07-27 15:31 ET - Street
Wire
“A diamond junior’s first task is to find a
kimberlite. The next and very important
step is to provide a convincing argument
as to why this kimberlite deserves a more
expensive bulk sampling to establish
carat grade”.
Quotation from John Kaiser, March 19, 2002
Introduction
Diamond grade is the most important parameter in assessment of a kimberlite pipe
There are two major obstacles for a correct assessment of a kimberlite:
* One of them is natural – irregular distribution of diamonds within a kimberlite pipe
* Another one is artificial – depends of method of assessment
Diamond grade variability: grade depends of a sampling location
(KV2 kimberlite, South Africa)
Irregular distribution
High grade areas
Barren areas
?
What about the “nugget effect?”
Irregular distribution Diamond grade variability: grade depends of a sampling depth
(KV2 kimberlite, vertical cross-section, South Africa)
It is easy to miss a rich diamond mine
200m
Camp, team, equipment, transportation… What if the target is wrong? It does not matter size, geometry and number of phases if kimberlite is barren. No point to go for stages 2, 3 and 4. We’re moving blindly from stage 1 to stage 2
Unsuitable method
Evaluation of a kimberlite pipe
“Diamonds are hard but brittle. Diamond loss due to the LDD lead to underestimation of diamond grade” P.Du Plessis, Shore Gold, 2009
Unsuitable method
There are three modes of evaluation of a kimberlite diamond grade: theoretical, practical &
scientifical
1. Theoretical: using partial chemical composition of diamond indicator minerals all with overlaps:
• Pyropes: CaO/Cr2O3 plot • Eclogitic garnets: Na2O > 0.07%,
TiO2 - FeO • Mg-ilmenite (flood basalts =
Noril’sk and Talnakh intrusions), • High-Cr spinels (ultrabasic
massifs = Kurung, Sudbury)
2. Practical: by microdiamond content
3. Scientifical (current research: by the whole chemical composition of garnets)Do not try to describe the
entire elephant having just a small piece of his tail
Wrong approach: an attempt to evaluate garnet composition (Mg, Fe)3 Al2(SiO4)3 by Cr2O3 & CaO which are an
accessory admixtures:
PYR = Cr2O3 ~ 5% + CaO ~ 5% (“the tail of the elephant”).
ECL: no interpretation on this chart. 90% of garnet composition are ignoredG 10 G 9
~ 30,000 grains
Wrong approach – wrong result: diamonds in Graphite Field – graphite in Diamond Field
Unknown areas ? Diamonds
or Graphite
???
Average diamond grade of eclogites from pipe Udachnaya, Russia,is 2,826,700 cpht (D.Schulze, 1997)
?
Graphite Field as well !!!
Bord
er b
etw
een
Gra
phite
and
Gra
phite
Fie
lds?
Where ?
Which kimberlite is better?
100 garnets from Ekati plot 12 dots within red oval while 300 garnets from
3.4 times richer Diavik plot 10 dots only. Must be: 12 x 3 x 3.4 = 122 dots
From Diamonds North presentation, Oct. 2009
Total grains ~ 100 Total grains ~ 300
12 10
G9G10 G10 G9
The Marsfontein M-1 Case (South Africa)
Originally M-1 kimberlite might be identified as non-economic based on poor population of G10 garnets on the Cr2O3-CaO chart. However, calculated peridotitic diamond grade (7.13 cpht), together with eclogitic grade (142.31 cpht) produced total grade as 149.44 cpht. Mining grade was confirmed as 148.58 cpht.
G10 G9
When is a G10 NOT a diamond indicator?
“The presence of G10 garnets… may not have any relationship to the diamond content of their kimberlite hosts.”
Quotation from: Nowicki & Gurney. Assessment of diamond potential using kimberlitic indicator minerals: key principles and applications. Greenland Workshop, 2005, Copenhagen.
Assessment of a kimberlite: What do we have now? The Past and the Present
2. Microdiamonds: practical approach
Superhard allotropes of carbon: diamond, lonsdaleite, fullerite, and moissanite
(SiC, hardness 9.5)
Lonsdaleite Mineral Data:Hexagonal “diamond” Chemical Formula: C Composition: 100.00 % CEnvironment: Associated with diamond in the Canyon
Diablo, Goalpara, and Allan Hills 77283 meteorites. Also in diamond-bearing placers.
Lonsdaleite is transparent brownish-yellow in color and has an index of refraction from 2.40 to 2.41, a specific gravity from 3.2 to 3.3.
Lonsdaleite is harder than diamond (B.Lam, 2009)
Fullerite Mineral Data:
Tetragonal “diamond”
Chemical Formula: C60
Composition: 100.00 % C
Locality:
Shunga area of Karelia, Russia. Meteorites and sediments derived from meteor impacts and the Tuvish basaltoid pipe at South Gissar,Tajikistan.
The hardness of ultra-hard fullerite at room temperature exceeds the hardness of diamond (V. Blank et al, 1998)
Extrapolation of microdiamond data
In case the red area is composed of lonsdaleite and fullerite only, what is the forecast for macrodiamonds can we expect within the yellow area? Data from: Pure Diamonds Exploration Inc. May 2006.
?
The Victor pipe was initially discovered before the Dia Met and
Aber discoveries in the Northwest Territories, but was put on the
shelf due to less than stellar initial (microdiamond) results.
Ultimately, over a period of many years it was established that a
portion of the Victor pipe had high quality coarse diamonds. Now
it is a De Beers $1 billion Victor diamond mine.
The lesson here is that poor initial microdiamond results may not
mean an economic deposit is not possible.
Alf Stewart. Diamond Exploration Tools. ResourceWorld. 2007
Microdiamonds failure
CONCLUSION
Using the current model of evaluation of
a kimberlite diamond grade we can not
get a correct outcome.
3. Scientifical (mathematical) approach
Assessment of a kimberlite:
What we could have now
Our Future
Two by Two will be Four
Forever…
Significance of a Correct Kimberlite Diamond Grade Data
“The Tli Kwi Cho (DO-27) fiasco”: The Northern Miner. 10/26/1998
“Tli Kwi Cho diamond pipe was discovered in 1993 and bulk sampled in 1994. Based on limited disclosures the market developed high expectations that were shattered when the bulk sample results were released. Overnight nearly a billion dollars in market capitalization evaporated as investors abandoned diamond companies.” “Angry investors claiming that the analyst and his clients had an unfair advantage.” John Kaiser, July 10, 2001.
“Well known grade disasters like Tli Kwi Cho, Torrie, Torngat and Wawa”:Kaiser Express 2002-04, “The Northern Miner” March 22, 2002
“Kennecott’s NWT, Tli Kwi Cho failure causes large sell-off of diamond stocks.”: James Dartnell, “Anatomy of a stock market winner”, 2003.
The bulk sampling of the DO-27 pipe in 1994 “did not produce the anticipated high grades, led to a catastrophic Canadian junior stock market crash and abandonment of the project”: Coopersmith, H., Pell, J., Scott Smith, B., 2006.
Evolution of Geological Models
Kimberlite Estimated Diamond Grade (feasibility study)(cpht)
True Grade(after mining)
Calculated Grade
MarsfonteinSouth Africa
335 308 242
Randgold Explor. 7th IKC S.Collingridge
Press Release Small Mines Wordsmith 1998 1998 1999
148.58SoutherneraAnn. Report
2000
149.44
UdachnayaRussia
120 100 Miller, P. “Diamonds” First Strike Yorkton Sec., 1995 Diamonds Inc.
60Eberle, J.M.
2003
65.01
Kimberley“Big Hole”
South Africa
100 15 Moon, C.J. Grizzly Diamonds 2006 2007
63.88
Generic Template Diamonds of
Africa
64.23
Finsch South Africa
80 49.30 43.99 before 1995 1995 Petra Diamonds Porter Geoconsultancy
36.33DBCM Report
2009
38.61
VictorCanada
10 23 38 30.22 Winzar, DJ, P.Gregory Worldwide De BeersReport 2001 Report Diam.Update 2008 2004 2004
No Data 41.53
DO-27Canada
1.3 1 36…89.88 L.Rombouts Boxer, G.L.1994 Peregrine Diamonds 1994 “Microdiamonds” 2005
No Data 71.42
Why these numbers are so different? Why these numbers are so close?
Notes for the previous slide
There is a principal question for the feasibility study results:
Why this feasibility study produced different data for the same kimberlite? Who is guilty for this, who is wrong?
Suggestions:
1. Feasibility studies were performed by perfectly trained professionals with B.Sc, M.Sc, Ph.D, P.Geo, P.Eng, P.Geol diplomas. Each of them is a QA/QC and a Qualified Person
2. They did their job in complete accordance with all rules and regulations which described by the National Instrument NI43-101.
3. Nobody is guilty, nobody is wrong. The System is wrong.
4. That is why many of diamond exploration companies have changed their orientation for gold, potash, base metals…
# Kimberlite[reference]
Country Predicted grade (cpht)
Final mining data,
(cpht)
1 Marsfontein, M-1[43] S. Africa 149.44 = 148.58 [4]
2 Klipspringer S. Africa 44.20 = 42.00 [5]
3 Kimberley “Big Hole” S. Africa 64.23 = 63.80 [6]
4 Finsch [34] S. Africa 38.61 = 36.33 [33]
5 Roberts Victor [47] S. Africa 132.99 > 100.00 [8]
6 Catoca [40] Angola 57.14 = 58.00 [64, 65]
7 Camafuca [7] Angola 6.72 = 5.84 [68]
8 K-14 [14] Canada 12.46 ~ 12.00 [26]
9 Mir [40] Russia 96.93 ~ 100.00 [40]
10 Aikhal [37] Russia 91.01 ~ 100.00 [66]
11 Udachnaya [15] Russia 65.01 ~ 60.00 [16]
12 Zarnitsa [15] Russia 17.52 ~ 15.00 [67]
13 Sytykanskaya [15] Russia 66.79 ~ 60.00 [17]
14 Lomonosova [38] Russia 75.85 = 70.00 [27]
15 Ellendale-4 [56] Australia 5.78 = 5.10 [57]
16 Garnet Lake [49] Greenland 107.37 ~ 100.00 [50]
Predicted Grade vs Final Mining Data
Predicted Grade by Source(Different sampling provided similar results)
Kimberlite, reference Country, region Predicted grade (cpht)
1). Victor, [9] Victor, [10]
Ontario, Canada Ontario, Canada
41.53 43.97
2). Gulf, [9] Gulf, [10]
Ontario, Canada Ontario, Canada
6.537.29
3). Udachnaya, [15] Udachnaya, [40]
Yakutia, RussiaYakutia, Russia
65.99 65.01
4). Yubileinaya, [15] Yubileinaya, [40]
Yakutia, Russia Yakutia Russia
71.2569.05
5). Botuobinskaya, [37] Botuobinskaya, [40]
Yakutia, Russia, Yakutia, Russia
86.87 97.32
6). Osenniaya, [15] Osenniaya, [40]
Yakutia, Russia Yakutia, Russia
61.1068.84
7). Komsomolskaya, [15] Komsomolskaya, [40]
Yakutia, Russia Yakutia, Russia
67.24 60.27 8). Yuzhnaya, [84] Pryazov’e, Ukraine
60.41 Yuzhnaya, [85] Pryazov’e, Ukraine 60.41
Concluding Remarks
Proposed a low cost universal revolutionary system can be used as a valuable exploration tool for quick and reliable calculation of real kimberlite diamond grade from any continent
It is proven to be over 90% accurate in predicting
the carats yield of sample ores based on the standard geochemistry of 100+ garnet grains extracted randomly from a kimberlite concentrate picked at any site within a kimberlite pipe; no special expensive analyzes needed.
It is possible to avoid slow, expensive and labour-
consuming current method of bulk sampling.
References (quotations)
1. Hi Igor,
Many thanks for sending me the copy of your diamond grade method. It looks great with excellent agreement for the mines where data is available. A nice piece of work.
Sincerely
Ken
Professor Kenneth D. Collerson,Establishment Director, Advanced Centre for Queensland University Isotope Research Excellence (ACQUIRE)Professor of Earth Sciences, The University of QueenslandBrisbane, Qld, 4072AUSTRALIA
Wed, May 19, 2010 2:10:32 AM RE: kimberlite diamond exploration
References
2. “Multivariate analysis of garnet compositions (Igor Kryvoshlyk,
personal communication) indicates that the diamond potential for
these kimberlites (Elliott county, Kentucky, USA) is very low (0-6
cpht). This is consistent with geothermobarometric calculations,
which suggest equilibration at relatively shallow depths (~26 kbar)
and high temperatures (>1100°C), well within the field of graphite
stability.”
Quotation from: GEOLOGY OF THE ELLIOTT COUNTY KIMBERLITE,
KENTUCKY. Prejeant, K., et al, Department of Geography &
Geology, Eastern Kentucky University. 2011 GSA Annual Meeting in
Minneapolis (9–12 October 2011) Paper No. 39-32
(quotations)
3. Igor, Most outstanding research! This is a cutting edge discovery that will revolutionize the diamond industry as we know it… This system of evaluation could prove to be very helpful
Perry KsyniukPresident Adamas Minerals Corp.Prince Albert, SK1 306 961 2824 cell1 306 764 0429 office
From: "[email protected]" <[email protected]>To: [email protected] Sent: Monday, January 23, 2012 12:10:38 PMSubject: Universal Diamond Exploration System UDES
References (quotations)
4. Original message (in Russian):
“Здравствуй Игорь,
Тут недалеко от Манчары в 6 км, разбурили еще одно кимберлитовое тело. Пока называется АН-10. Спектр гранатов несколько отличается от Манчары. Если тебе интересно, посчитай по своей методике. Мне кажется она очень перспективная”
Translation:
“Hello Igor,
Not far from Manchary (kimberlite, Yakutia, Russia), in 6 km, the another kimberlite body is discovered. So far they call it AN-10. Garnet spectrum is a little bit different from Manchary. If it is of interest for you try to calculate it (diamond grade) using your method. It seems a very perspective to me”
Dr. A. P. Smelov Former Director, Diamond and Precious Metal Geology Institute, Siberian Branch, Russian Academy of Science. Yakutsk, Russia. E-mail: [email protected]. Phone: (4112) 44 57 14Sunday, May 13, 2012, 7:25:20 pm
References (quotation)
References (quotation)
Regards,
Patrick Cheetham, Executive Chairman, Sunrise Resources plcSilk Point, Queens Avenue, Macclesfield, Cheshire SK10 2BB, United [email protected] Direct line: +44 (0) 845 868 4582Switchboard: +44 (0) 845 868 4590Fax: +44 (0) 845 838 559
5. Igor,
You are right - there is no way to be sure any calculations are correct until the project is mined (as with all estimates) and in this case we may never know…but your estimate in this case is consistent with our own thoughts about this kimberlite based on multiple sources of information.
I am intrigued by your methods and…I would be interested to use it in future as a corroborative tool.
6. Hello Igor, following a preliminary look at your paper it looks extremely interesting… …Again, thank you for a most interesting paper which I will enjoy studying in detail…
Peter Gregory. Owner, Lonart Pty Ltd. Pert Area, Australia.
Email: [email protected]: Friday, July 19, 2013 10:25:47 PM
References (quotation)
References (quotation)
7. Dear Igor,
Thanks for calculations you made for Ermakovsky kimberlite. The data are very
interesting and worthy to be known by Russian geologists. That is why I suggest
to write the short paper with your co-authorship on Kola and Ukrainian "low-
grade" or "barren" kimberlites and their reassessment using your calculations.
Best regards,
Dmitry Zozulya
Senior research scientist
Geological Institute
Kola Science Centre
14 Fersman St, 184209 Apatity
Russia
Peter Gregory. Owner, Lonart Pty Ltd. Pert Area, Australia. [email protected], July 21, 2013 4:13:13 AM
8. Hello Igor, some most intriguing and original hypothesis. The kind of
“spacial” thinking is something Russian scientists are very good and I’ve
seen interesting maps produced by them in Siberia but nothing quite as
good as your ideas…
…Most interesting work and ideas you have, thank you for sharing them…
…Again, thank you for a most interesting paper which I will enjoy studying in detail…
References
9. Dear Igor,
Your System is so revolutionary !
You're a thinker from another planet !
Verdi Scholtemeyer, Director of Kimberlite Explorations
Brookfield Diamond Mining & Esanro Kimberlite Explorations
Embalenhle Area, South Africa
Mon. July 29, 2013 at 3:34 AM
E-mail: [email protected]
References
Reference 1. Dear Igor Kryvoshlyk,
My name is Bram Janse… As many other diamond exploration geologists I have been struggling to
understand the worldwide distribution of diamondiferous kimberlites and constructed maps with many photo lineaments, circles, zones, etc. but never achieved a satisfactory result…
…I was impressed by your spiderweb especially the construction of polygons to define favourable areas within a field… I like your garnet diagram. It does achieve a clear separation of eclogitic garnets which has always been a sore point…
With sincere regards, Bram Janse. (Bram is a distinguished geologist and chartered engineer internationally recognized for his expertise and long-term association with the diamond exploration industry. His experience spans more than 45 years of mineral exploration, specializing in diamond exploration on all continents .) Paramount Mining Corporation Ltd(618) 93285600 Ph(618) 93284430 FAX
Sun, March 15, 2009 3:41:43 AM