First Discovery of Carbonatite in India
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ever, their carbonatitic nature has been ruled out by the authors who studied these rocks. Gwalani et al. (1993) studied Bakhatgarh and concluded that these rocks “may be carbonate-rich breccia “, while Hari et al. (1998) interpreted these as “Carbonate-rich dike rocks” but not true carbonatites. It is clear, therefore, that Bose did not report in 1884 the first discovery of carbonatite in India, and Högbom (1895) should not be denied credit for proposing that the carbonate rocks of Alnö in Sweden are magmatic, although recognition as the first to introduce the name ‘carbonatite’ remains with Brögger (1921) for his study of the Fen complex in Norway. While it remains incontestable that Sukheswala and Udas (1963) reported Amba Dongar in Gujarat as the first discovery of carbonatite in India it must also be noted that as early as 1960 Sukheswala, visited Amba Dongar in his role as a consultant for a private mining company interested in its fluorite potential, was convinced that the rocks he was examining were carbonatites. He revealed this in his key note address to the Carbonatite-Kimberlite Conference organized by the Geological Society of India at Bangalore in 1976 (Sukheswala, 1976). He wrote “In 1960 when I first visited Amba Dongar in connection with fluorite prospecting for an industrial concern, I was baffled by the intrusive nature of the carbonate rocks, later identified as plugs of ankeritic carbonatite, and also their radioactive character. These features, further substantiated by the geochemical data, helped us to establish the area as carbonatitealkalic complex, the first such find in India (Sukheswala and Udas, 1963)” While stating that Bose was not the first to describe carbonatite in India his geological contribution to Indian geology in the Lower Narbada Valley is immense. His account of the ‘agglomerates’; of the area around Kawant, Siriwasan, Mankui and Mongra remain the best guidelines for all subsequent study. These outcrops of agglomerate in Siriwasan were subsequently described by Sukheswala and Borges (1975) as a ‘Carbonatite breccia sill’ Prior to Bose in 1884, Blanford (1869) published his account of the ‘Geology of the Taptee and Lower “Nerbudda” Valleys and some adjoining districts including Mongra and Padwani. However, most important is that the name ‘Ambadoongur’ appeared for the first time in 1869 in Blanford’s description of rocks in the Lower Narmada Valley. He suggested that sandstone boulders at Hamp (now named as Hampeshwar) had rolled down from ‘Ambadoongur’. He did not, however, reach the Amba Dongar carbonatite. It is to hoped that the controversy about the first discovery of carbonatite in India can now be laid to rest. It might be noted that Heinrich, in his book, exercised a rather liberal interpretation of what constitutes a carbonatite including many that would not generally be agreed, particularly in Canada (personal comment by Prof. John Gittins). Acknowlegements: I am grateful to John Gittins for comments and suggestions 623
References Blanford, W.T. (1869) On the Geolo
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