Host Rock (母岩)
Host rock (also known as wall rock) is a rock that is used as a base for something.
Earth and planetary science
Rock that forms mother body which surrounds the focused materials, such as useful mineral and hot spring. There is a lot of mineral deposit that is contained only in a specific host rock such as diamonds in kimberlite.
Archaeology
Stone (ore) that is used for making stone tools. In many cases stones lying around or stones in a riverbed are used, however, the stones that could be produced only in the limited place, such as obsidian, shale and sanukite would be not only collected from the ground but also mined. Some host rocks could be used as stone tools without being processed, and these rocks were called pebble tools.