Shaft mining or shaft sinking refers to the method of excavating a vertical or near-vertical tunnel from the top down, where there is initially no access to the bottom.
When the top of the excavation is the ground surface, it is referred to as a shaft or portal; when the top of the excavation is underground, it is called a winze

Winze

A winze is an opening in an underground mine that is sunk downward from inside to connect lower levels. The top of a winze is located underground, in contrast to a shaft where the top of the excavation is located on surface....

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The mine shaft is used to gain access to an underground 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...

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