Ahead of the first offshore mineral auctions, the central government has introduced royalty rates for construction sand, polymetallic nodules, and overburden or waste—key minerals to be extracted through offshore mining. The royalty rate for dolomite has also been slated for revision. This comes as the Centre prepares to bring 20 blocks for auction in the coming months. The royalty rates, defined under the Offshore Areas Mineral (Development and Regulation) Act, 2002, were initially limited to a few core minerals, including brown ilmenite (leucoxene), ilmenite, rutile, zircon, dolomite, garnet, gold, limestone, lime mud, manganese ore, monazite, sillimanite, and silver.