The Rajasthan High Court last week dismissed a batch of writ petitions moved by about 20 mining companies challenging the amendment to the mineral concession rules under which they had to pay more to the state. The mining companies, led by Khaitan Chemicals and Bhilai Engineering Corporation, argued that the amendment permitted notional determination of the sale price by adding 20 per cent of the benchmark value, and it was beyond the powers of the central government. They contended that the authority of the central government under the Mines and Minerals Act was limited to the extent of fixing and