What is the name of the horizontal tunnel drilled through a diamond pipe?

The correct answer, "drift," refers to a horizontal tunnel that is typically excavated through a diamond pipe or similar geological formation to access the minerals found within it. In mining terminology, a drift is specifically designed to navigate and explore the mineral-bearing rock, often running parallel to the ore body.

Drifts are essential for the extraction process because they allow miners to reach specific areas of interest within the diamond pipe without extensive vertical excavation, which can be more complex and costly. The creation of a drift facilitates access for both exploration and mining operations, making it a fundamental part of underground mining procedures.

In contrast, the other options represent different aspects of mining and excavation techniques. A stope is a step-like excavation formed during the extraction of ore, a shaft is a vertical passageway used to access deeper levels of a mine, and a cave refers to a broader geological formation or a mining method involving controlled collapses for ore retrieval. These terms highlight various methods of accessing and retrieving minerals but do not specifically denote a horizontal tunnel as the drift does.