Exploration for Rare Earth Elements Mineralization in Amba Dongar Carbonatite, Gujarat, India: An Overview and Some Suggestions

Total REE reserves in India are about 6% of the Global reserves, however, this figure will definitely go up after obtaining the results of explorations in call carbonatite complexes of India. The Amba Dongar carbonatite was discovered in 1963 by Sukheswala and Udas. They were the first to note the importance of REE in this complex and reported an average of 1.04% RE2O3 in carbonatites. Over the past seven years, large-scale exploration has been launched by the two prime organizations; Atomic Minerals Divisions, DAE, India, and the Geological Survey of India for Rare Earth Elements. Since then, many publications have discussed REE deposits related to the Amba Dongar Carbonatite and have given the estimate of total REE deposits in Amba Dongar. Recent publications report REE ores of around 105 Mt tons at 3% RE2O3. So far, the exploration has been restricted to only the Southwestern part of Amba Dongar, and that too only in easily accessible areas. The writer of this paper is therefore, of the opinion that at this early stage of exploration, the estimated averages are far from the total budget of REE in the Amba Dongar complex. REE minerals occur both as magmatic and hydrothermal stages and are located all over the outcrops of carbonatite breccia, sovite, and ankeritic carbonatite albeit in certain areas of rich mineralization. Amba Dongar diatreme has very complex geology and structure and therefore it calls for a more detailed study including a geophysical survey before the total assessment of the REE budget is presented. Some suggestions have been made in this regard for precise exploration targeting.