lump ore

mining

Also known as: rubble ore

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Last updated

June 30, 2026

Quick Summary

Iron ore is a natural aggregation of minerals that can be mined and sold for profit, with hematite, magnetite, limonite, and siderite being key sources of iron. Most iron ore is extracted through surface mining, which is more economical than underground mining.123

The mined ore contains lumps of various sizes. For use in a blast furnace, the ore needs to be crushed into specific sizes, typically between 7 and 25 millimeters. This process separates the desired "lump ore" from smaller "fines". Fines must be reformed into larger pieces through a process called sintering, which involves heating them until they fuse together.23

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iron processing
Lumps and fines
As-mined iron ore contains lumps of varying size, the biggest being more than 1 metre (40 inches) across and the smallest about 1 millimetre (0.04 inch). The blast furnace, however, requires lumps between 7 and 25 millimetres, so the ore must…
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As-mined iron ore contains lumps of varying size, the biggest being more than 1 metre (40 inches) across and the smallest about 1 millimetre (0.04 inch). The blast furnace, however, requires lumps between 7 and 25 millimetres, so the ore must…
Read More