  In this paper we analyzed dependencies in commodity markets investigating
correlations of future contracts for commodities over the period 1998.09.01 -
2007.12.14. We constructed a minimal spanning tree based on the correlation
matrix. The tree provides evidence for sector clusterization of investigated
contracts. We also studied dynamical properties of commodity dependencies. It
turned out that the market was constantly getting more correlated within the
investigated period, although the increase of correlation was distributed
nonuniformly among all contracts, and depended on contracts branches.
