The Research Group of Dr. Arundhuti Ghatak, Department of Earth and Environmental Sciences, narrated the occurrences of critical minerals, namely the pyrochlore group of minerals in the carbonatites (niobium-hosted mineral) from the Saidiwasan Complex, Gujarat, India. These Early-formed magmatic pyrochlore groups in Saidiwasan carbonatites are characterized by high calcium, niobium, fluorine, and sodium content, subsequently replaced by secondary cation-deficient grains due to supergene weathering processes. These alterations manifest predominantly at the A site and occasionally at the B site, and involve the substitution of fluorine with hydroxide (OH-) groups. During alteration, calcium and sodium are leached from the pyrochlore structure, with charge balance maintained by the substitution of Rare Earth Elements (REE), Th, U, Ba, or Sr. In the later supergene stages, marginal and fractured zones of pyrochlore grains experience metamictization, resulting in Pb-rich and cation-deficient hydrated varieties. Mohanty and Ghatak et al., 2025, for the first time, tried to identify the alteration and narrated the substitution reactions for the leaching of the REE from the pyrochlore group and resulting in the formation of monazites (a REE-phosphate mineral). For more details, kindly visit. https://doi.org/10.1002/gj.70025