ROBERT SORBY THIN BLADE PARTING TOOL
The 1/16 in. thick blade allows for very fine parting, useful where grain match is required.
ie. boxes, vases etc.
Used long edge up, can be sharpened with a fine stone, but using a light touch on the grinder gives a useful little burr which cuts a cleaner edge.
Some turners sharpen the short bottom edge to a slight curve (like the bow of a boat) and extend this edge towards the middle of the blade.