Undercutting at the King Mine of Asbestos Corporation, Limited
The purpose of an undercut is to undermine a block of ore which will then proceed to cave into draw holes just below the undercut. Undercutting is the final and most vital phase in the development of an ore block. Since its purpose is to undermine and induce caving into a block of ore, great care must be exercised to avoid premature caving by removing only enough rock to permit undercut development to proceed. Several undercutting methods, used over a twenty-year period, are reviewed and their suitability is compared with ideal requirements.