It leaves a cylinder shape which often is used as sink holes or to feed lines and pipes.
Marble hole drill bit.
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Marble core bits are a hollow cylindrical bit that is the cutting part of a core drill.
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Rather than relying on channel action like normal bits core bits have a central pilot bit that holds the bit in place while the outer sections of the bit cuts a hole through stone.
These core bits are made up of a concentration of diamonds and metal bonds in order to cut the hard surface of the granite.