Jerusalem stone is the name for the various stones found in and around Jerusalem, Israel, that have been used in construction since ancient times. Some of these stones include limestone, dolomite, and dolomitic limestone. The limestone, meleke, according to Wikipedia has been used in many of the region's famous structures including the Western Wall.
Jerusalem is the holiest city in the world. Within Jerusalem, the holiest spot is where the Holy of Holies once stood in the Solomon's Temple of Jerusalem. This spot is currently under the Dome of the Rock. This spot is called the Foundation Stone, where G-d brought forth all creation as written in Scriptures in the Book of Genesis.
Enjoy this video describing the ancient Jewish history of Jerusalem.