New Delhi, Nov. 13 -- The Union Cabinet, chaired by Prime Minister Narendra Modi, on Wednesday approved new royalty rates for four key critical minerals - graphite, zirconium, rubidium and caesium - in a bid to increase domestic production, reduce import dependence and attract fresh investment in the mining sector. "There are some critical minerals available in the country whose royalty structure needs to be changed. A very high royalty was imposed on these materials, so that has been reduced to increase their production," said Union minister of IT, railway and I&B Ashwini Vaishnaw at a press briefing after the cabinet meeting on Wednesday. Under the revised structure, the royalty for graphite will now be calculated on an ad valorem basis i...