The bolts are then further split or ‘riven’ into pieces, carefully laying out each split and using the material as efficiently as possible. Finer riving is done using a tool known as a froe. The froe is a long, thin wedge with a perpendicular wooden handle. After pounding the froe into the end grain of the wood, it is levered back and forth along the split, providing the craftsperson with better control of the split.