Dragged down by RIL and Coal India, the combined market valuation of top-eight Sensex companies nosedived by Rs 58,504 crore last week.

Barring IT majors, TCS and Infosys, eight of the top 10 blue-chips that also included HDFC Bank, ONGC and SBI saw losses in their market capitalisation (m-cap) for the week ended March 1, in an overall weak stock market.

The BSE 30-scrip index, Sensex, fell by 2 per cent to end the week at 18,918.52.

The m-cap of RIL plunged Rs 16,590 crore to Rs 2,61,916 crore, making it the biggest loser among the top-10 companies, as its scrip dropped by over 6 per cent to Rs 809.50.

Coal India's value tanked Rs 11,464 crore at Rs 1,98,460 crore, while HDFC Bank lost Rs 9,157 crore at Rs 1,47,352 crore.

M-cap of ONGC dipped Rs 7,871 crore at Rs 2,69,369 crore, while SBI took a hit of Rs 7,193 crore to decline to Rs 1,40,201 crore. ICICI Bank's value diminished by Rs 4,072 crore, to Rs 1,21,841 crore.

NTPC saw an erosion of Rs 1,361 crore from its m-cap which was at Rs 1,23,434 crore, while ITC's value fell by Rs 796 crore, to Rs 2,29,289 crore.

In contrast, TCS added Rs 8,827 crore taking its m-cap to Rs 2,93,495 crore, while Infosys' value shot-up by Rs 4,127 crore to Rs 1,67,013 crore.

In the domestic market-cap chart, TCS continued to remain at the numero-uno position, followed by ONGC, RIL, ITC, CIL, Infosys, HDFC Bank, SBI, NTPC and ICICI Bank.