Global metals and mining companies saw a median decline in market cap of 1.2% overall during August. The top 25 miners had an aggregate market cap of $687.76 billion at the end of August, down 5.8% from July. Similarly, the SNL Metals & Mining Index dropped 5.8% during the month.

Fourteen miners saw declines in market cap, while 11 experienced gains during the month.

Much of the decline came from diversified metals and mining companies, with seven of eight of those losing at least 3% during the month. Gold producers largely saw improvements, with eight of nine gaining at least 2% as the price of gold is expected to gain momentum in the second half of 2019.

The largest increase of the month was Shandong Gold Mining Co. Ltd. with a 27.5% rise in market cap, climbing five spots to 15. The Chinese gold miner reported a 9% increase in year-over-year profit in its interim report.

The second- and third-largest increases were also gold producers. Toronto-based Agnico Eagle Mines Ltd. and Barrick Gold Corp. saw a 21.1% and 18.9% rise in the market cap, respectively, during August. Agnico Eagle Mines climbed four spots while Barrick Gold rose two. Both were among the largest gold producers during the second quarter.

One of the largest copper producers, Freeport-McMoRan Inc., saw the largest decline in market cap at 16.9% and fell five spots from July's ranking.

Vale SA was hit by the second-largest decline; despite the 16.8% drop in the market cap, Vale's ranking remained unchanged. Moody's recently raised its outlook on Vale to stable from negative.

Anglo American PLC continued to see a drop in market cap, at 15.9%, losing two additional spots.