Most carvers create a sculpture from a single piece of argillite wherever possible. However, because an increase in the size of argillite increases the potential for failure in the piece due to inherent faults and stresses, larger sculptures are sometimes made from separate pieces carved and subsequently adhered. High relief is often carved by working against the grain. This technique lends stability to the fragile argillite. The drawback to this method is that it sometimes causes flaking, making carving in high relief an advanced carving technique. For a long, shallow piece, it is often better to work with the grain. Different objects require varying levels of skill in their execution. Panel pipes are considered the most difficult pieces to carve. Bowls are also challenging, with group figurines, boxes, poles and plates considered easier to do. The black finish of argillite is usually not natural. In its natural state, argillite is often a grey-black or green-black color. The jet-black finish is created by the carver rubbing the carving with the oils or polish as it is being created. The natural oils that skin produces are actually responsible for creating the deep black color argillite is known for, although it is also common to coat the argillite with a polish to recreate the jet-black color.
