A brattice is a partition used in mining

Mining

Mining is the extraction of valuable minerals or other geological materials from the earth, from an ore body, vein or seam. The term also includes the removal of soil. Materials recovered by mining include base metals, precious metals, iron, uranium, coal, diamonds, limestone, oil shale, rock...

. It is built between columns of a sub-surface mine to direct air for ventilation. Depending on the type of mine and how the operation is run, brattices can be permanent (concrete block, tailings, or wood) or temporary (cloth). Temporary installations are also called curtain

Curtain

A curtain is a piece of cloth intended to block or obscure light, or drafts, or water in the case of a shower curtain. Curtains hung over a doorway are known as portières...

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