In general, the secondary superficial deposits of sulfide ores is observed following zoning: a surface layer of oxidized ore subzone, Subzone oxidized and leached ore subzone rich oxidized ore zone of secondary enrichment of sulfide ores and the zone of primary sulfide ores.
For iron ore deposits characterized by the formation of deposits on the surface of ironstone (limonite), which in the final stage of oxidation assumes all iron minerals. And  deeper

  this zone is often located leached zone. Below, may lie loose secondary sulfides, and below them the primary sulfide ore.
Not always superficial accumulations ironstone signal about finding underneath is iron ore. Ironstone formed in the oxidation zone in the expansion of chalcopyrite copper deposits and the expansion of pyrite, almost always accompanies most other fields, so under the so-called "iron hat" can be detected by a variety of ore deposits.