low4. Exploration strategy of iron ore specifically for low-grade hematite in the light of cutIBM report on new cut-off grade. Observation of GSI: Total resources potentiality of hematite iron ore is yet to be known in the country. Currently the resources and reserves are calculated based on arbitrary 55% Fe as cut off to produce mineable ore (the lowest grade, which can be economically exploited at a particular time, is the cut off grade). The level of cut off grade varies and is determined by market conditions keeping obviously the conservation point in view, as these are non-renewable resources. As a result, earlier, enriched banded iron formation (BIF) containing 45-55% Fe was not considered as ore. New, development of ore enrichment techniques has made the use of lower grade ore possible. The quantum availability of such type of ore was never estimated in the past as these were considered as non-ore. The assessment of the new prospects and re-assessment of the existing mines is a must to optimize production, to cater to the demand of the market, based on economic grade and scheduling. Such exercise would obviously enhance the resource base to a great extent. In lease free, non – forest areas, assessment of low-grade iron ore (+45% Fe) is being undertaken by GSI to augment resources at both 45 and 55% cut off grade. GSI would initially (through P I and P II stage investigation) identify new areas with UNFC-G4 type resources and wherever needed (through E-I stage investigation) establish UNFC G-3 type resources of hematite iron ore of +45% and +55% Fe, separately. Along with exploration, petrological studies also will be taken up to find out mineralogical assemblage to establish suitability of low-grade iron ore for beneficiation. As almost entire quantity of hematite iron ore is confined to Orissa, Chhattisgarh, Jharkhand, Karnataka, Maharashtra and Goa programme will be initially restricted in the potential geological domain of these states which will be extended to M.P. and A.P subsequently. This is expected to be completed in a five to seven years time frame based on availability of manpower. Upgradation of resources from 334 to 333 categories will be a continuing process. Magnetite is also an important ore of iron. Magnetite ores are generally restricted in Karnataka, Tamil Nadu, Kerala, Andhra Pradesh, Goa, Rajasthan and Assam. Small resources have been established in other States also. As per IBM year book 2006, total resources of magnetite ore in the country is 10.61 billion tones of which reserve is only 58.50 million tones and the rest is resource. Out of total resources, 6.28 billion tones is under 333 category of UNFC system. There is ample scope to carry out regional exploration for magnetite ore in the country. This will include tracing of BMQ bands with or without scout boreholes as well as exploration by drilling of partly explored/unexplored large deposits which will bring additional resources under 334, 333 and 332 categories of UNFC system. At present GSI is engaged in two items of magnetite ore exploration, one each in Tamilnadu and Rajasthan.
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IBM and the State Governments of iron rich states are requested to provide the lease status along with latest maps showing the lease boundary under different concessions (PL, ML) to the GSI for mounting low-grade iron ore assessment programme in the country. Forest overlay map also may kindly be provided to finalize the exploration programs for GSI. Earlier IBM provided 1:100000 scale mining lease map for some of the iron rich states. Now IBM is requested to provide 1:50000 scale maps showing all the concessions and forest areas. It is strongly felt that the exploration programme will be affected to a great extent where drilling will be involved in forest areas. A clear cut dialogue has to be established with MoEF on the issue of regional exploration in forest areas so that uninterrupted exploration programme can continue for evaluating total resources of iron ore of all grade in the country irrespective of forest cover. A new agenda has been given by IBM which states “Proposal for GSI to Proposal lowundertake matching revaluation of low-grade iron ore resources in freehold areas in India” i.e. GSI need to carry out exploration in lease free areas (which has already been detailed above). IBM will be carrying out revaluation in the leasehold areas. In this connection, it may be noted that the task is huge and requires additional exploration to come to any meaningful resource evaluation. In the leasehold area, low grade (+45% Fe) iron ore occurs in one of the following modes: i) As partings within high grade ore (Shaly ore) ii) In the hanging wall or footwall side of ore zone or as separate bands iii) on top in the lateritic profile (lateritic and limonitic ore), iv) As the bottom of established ore within zone of enrichment above proto ore. Exploration of data are likely to be available for lateritic profile and partings because such zone were intersected during earlier exploration but fresh data have to be generated for evaluation of the low grade ore occurring at hanging wall, footwall and bottom of existing ore zones. This will require a well-designed exploration programme. It may also be noted that India had 474 mining leases as on 1.3.2004 and during the period from 2004 onwards Ministry of Mines, Government of India has approved 146 PL applications and 184 ML applications for iron ore. These figures clearly reflect that bulk of the iron ore deposits/prospects are either under mining lease or under prospecting license. This scenario is due to iron ore mining boom, which existed before the global cash crunch. In all these leasehold areas where maximum availability of iron ore resources are locked in, proper data evaluation is needed to examine the reserve and resource balances and examine whether the exploration was done in totality or there is scope to augment reserves/resources with lower cut off through further exploration. Total exploration data in the leasehold area have to be evaluated and a decision to be taken whether IBM will be able to generate further exploration data for total evaluation of low-grade iron ore. Lessee will have to play a major role in this regard to generate proper exploration data for total resource evaluation. IBM may come out with a detailed plan with time frame.
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