ENRC's founding trio of major shareholders are collectively about $100m (£66m) out of pocket after a $1.5bn charge plunged the Kazakh-focused miner into the red last year.
The FTSE 100 copper, iron ore and aluminium group reported a $550m loss for 2012 against a $2.76bn profit in 2011, after rising costs and falling prices cut sales by 18 per cent to $6.32bn and forced the charge. ENRC scrapped its final dividend, meaning payouts for the year were just 6.5 cents a share, against 27 cents in 2011. ENRC's founders, Alexander Machkevitch, Patokh Chodiev and Alijan Ibragimov, saw the full-year dividend on their 38 per cent stake plunge to $32m from $132m.
The miner is considering issuing new shares as it looks to cut $5bn of debts racked up after a six-year acquisitions spree.
Felix Vulis, chief executive, said he was in talks with investors over a possible share issue. He added: "We have five major shareholders. Their decision will be important for us to proceed. We, as a management, are fully committed to remaining in the FTSE 100, and that process has been started."
ENRC's $1.5bn charge included writedowns of $608m on the value of its aluminium unit in Kazakhstan, $240m on its Boss copper and cobalt mine in the Democratic Republic of Congo, and $96m from Chambishi, the Zambian copper and cobalt smelter acquired in 2010. It also wrote down $120m from the value of its 13.5 per cent stake in Johannesburg-listed Northam Platinum, and booked a $328m charge related to a now-unprofitable contract to supply alumina to Rusal in Russia.
Mr Vulis said: "2012 was a challenging year for the group, with deteriorating prices having materially impacted our earnings."
Shares in ENRC fell by 5.8p, or 2 per cent, to 306.9p.