Anglo American has announced that the bulk of its iron ore division, which accounts for around half of group profits, saw earnings drop in the first half.The 69.7%-owned Kumba Iron Ore unit, a South African supplier of seaborne iron ore which is listed on the Johannesburg Stock Exchange, contributed just $409m to the Anglo's underlying earnings in the six months to June 30th, down from $579m the year before.The decline came despite iron ore production growing 5% over the year to 22.8m tonnes following a solid performance at Kumba's Sishen and Kolomela projects.Kumba generated an underlying operating profit of $3.05bn in 2013 - the majority of the $3.12bn from the whole iron ore and manganese division - accounting for nearly half of the the $6.6bn Anglo made as a whole during the year.Underlying earnings from Kumba came to $1.12bn last year; Anglo's underlying earnings were $2.7bn.BC