Dec 5 (Reuters) - The Baltic Exchange's main sea freight index, which gauges the cost of shipping bulk commodities such as iron ore, grain, coal and fertiliser, rose for the ninth straight day on Thursday, as capesize rates jumped. * The overall index, which factors in the average daily earnings of capesize, panamax, supramax and handysize dry bulk transport vessels, gained 151 points, or 7.57 percent, to 2,145 points. * The Baltic's capesize index rose by 362 points, or 10.4 percent, to 3,843 points. * Average daily earnings for capesizes, which usually transport 150,000 tonne cargoes such as iron ore and coal, were up about 16 percent or $4,576 to $33,475. * The Baltic's panamax index gained 72 points, or 4 percent, to 1,867. * Average daily earnings for panamaxes, which usually transport 60,000-70,000 tonne cargoes of coal or grain, rose $574 to $14,912. * Shipments of iron ore account for about a third of seaborne volumes on the larger capesizes, and iron ore price developments remain a key factor for dry freight. * The dry bulk market continues to heat up, contrary to many market participant expectations for the final month of 2013, said Omar Nokta, an analyst with GHS Securities. * More consistent charterer demand amidst an increasingly thin vessel supply is propelling capesize rates, Nokta said.