A new pyrope-based mineralogical-petrological method for identifying the diamond potential of kimberlite/lamproite deposits

Southern West Greenland hosts a province of ultramafic alkaline rocks, including swarms of dykes traditionally described as kimberlites and lamproites (Larsen 1991; Jensen et al. 2002). Since the mid-1990s, commercial diamond exploration has been focused on the Sarfartoq region and the region south-east of Maniitsoq (Fig. 1), and has resulted in numerous reports of diamond-favourable indicator minerals from till sampling, finds of kimberlitic dykes, and recovery of diamonds from kimberlitic rocks. A new digital compilation of company data released from confidential status (Jensen et al. 2003a) presents a comprehensive overview of exploration activities and results that have emerged since the Survey’s first compilation of occurrences of kimberlitic and related rocks (Larsen 1991). The new compilation in a GIS (geographic information system) environment allows for refined assessment of the distribution, structural control and possible spatial and petrogenetic relationships that characterise the kimberlitic occurrences. In 2003, the Geological Survey of Denmark and Greenland (GEUS) and the Government of Greenland’s Bureau of Minerals and Petroleum (BMP) went further than has been customary in investigating the economic potential of specific sites. Four areas were temporarily closed to application for exploration licences, pending sampling and testing for diamond content of large samples of more than one tonne each from significant kimberlitic occurrences. Additional characterisation and research initiated on these and other occurrences include magnetic mapping, detailed petrography and studies of mantle xenoliths, as well as indicator mineral chemistry. An extensive programme to determine the ages of kimberlitic and related rocks was also initiated in 2003.

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Diamond potential of metamorphic rocks in the Kokchetav Massif, northern Kazakhstan

European Journal of Mineralogy ◽

10.1127/0935-1221/2008/0020-1813 ◽

2008 ◽

Vol 20 (3) ◽

pp. 395-413 ◽

Cited By ~ 18

Author(s):

Victor A. Pechnikov ◽

Felix V. Kaminsky

Keyword(s):

Metamorphic Rocks ◽

Kokchetav Massif ◽

Northern Kazakhstan ◽

Diamond Potential

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Ratio of structural impurity distribution in diamond crystals and kimberlite pipe diamond potentiak (case study of Arkhangelsk region and Yakutia)

Ores and metals ◽

10.47765/0869-5997-2021-10023 ◽

2021 ◽

pp. 114-130

Author(s):

Galina Khachatryan ◽

Nataliya Anashkina

Keyword(s):

Kimberlite Pipe ◽

Impurity Distribution ◽

Low Grade ◽

Arkhangelsk Region ◽

Negative Factor ◽

Diamond Crystals ◽

Thermodynamic Conditions ◽

Structural Impurity ◽

Diamond Potential

IR spectroscopy was used to compare diamonds from 12 pipes, Arkhangelsk region. Based on positive correlation between average N and H values in diamonds from various deposits, it was found that crystals from low-grade diamond pipes are relatively enriched in hydrogen compared with diamonds from Lomonosov and Grib deposits. In terms of structural impurity distribution, Arkhangelsk deposit diamonds differ from Yakutian diamonds; it could be due to various composition of compared diamonds’ source matter and thermodynamic conditions of their growth. It is shown that hydrogen is a negative factor of diamond potential in both Yakutian and Arkhangelsk diamonds. This can partly be explained by impuri-ty blocking effect on diamond crystal growth.

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Diamond study features in forecasting and prospecting (Siberian platform)

Ores and metals ◽

10.47765/0869-5997-2021-10018 ◽

2021 ◽

pp. 59-75

Author(s):

Nikolay Zinchuk ◽

Leonid Bardukhinov

Keyword(s):

Siberian Platform ◽

Morphological Criteria ◽

Diamond Potential

Based on the completed research and data summary on diamonds specific features (an example from the Siberian platform), conclusions were made that indications exist at all levels of their location: from kimberlite-related provinces, subprovinces, fields, diatremes to ore shoots. Population of diamond varieties in kimberlite rocks forms parasteric, rather than paragenetic, associations related to their coexistence in kimberlites. Morphological criteria of kimberlite diamond potential were defined depending on rounded diamonds content in them. Significant differences in kimberlites diamond potential were not revealed to the explored depth of diatremes. A conclusion about the absence of horizontal concentric zonality in the change of diamond typomorphic features was made.

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