India's deep-sea mining causes a stir
The Indian government, which has spent about US$40 million surveying the site, estimates that reserves of the nodules — which are rich in manganese, copper, nickel, cobalt and iron — could be worth as much as US$200 billion.
But researchers at the National Institute of Oceanography in Goa, who undertook a survey to assess the environmental impact of mining operations, warn that discharges of unwanted sediment during mining will upset the area's ecological balance.
Reference: Nature 417, 212 (2002)
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