Glencore Xstrata's shares declined following reports the miner may write down the value of assets inherited from Xstrata by as much as 7.0bn dollars when it reports its half-year earnings this week.The company will on Tuesday unveil its first set of results since Glencore's takeover of Xstrata in May.Glencore's management has been reviewing Xstrata's assets over the past three months.The writedown, mostly on the value of former Xstrata assets, is expected to amount to $5.0bn to $7.0bn, analysts and industry sources told Reuters on Sunday.Nickel assets are likely to take the biggest hit as nickel prices decline and supply continues to exceed demand.The value of other assets including copper projects could also be cut back even though it accounted for a large slice of Xstrata's pipeline of future mines and expansions.Glencore declined to comment.The company expects half-year core profit, or earnings before interest, tax, depreciation and amortisation (EBITDA) to come to $5.88bn, and attributable profit to reach $1.7bn.Shares were down 1.95% to 302.35p at 09:50 on Monday.RD