Ban Nagura is a coarse grade of stone, usually used for sharpening tools like sickles and scythes and other similar edged implements. Ban may be used successfully for sharpening finer edges like scissors and cutlery, but care must be taken; it is an inconsistent abrasive, and there are many large and harder particles to contend with. Ban is usually white, with a yellow hue through the stone. Often, there are yellow spots dotting the landscape, some of which are harder than others. The oldest Ban will be creamy yellow; sometimes there will be blue/grey streaks running through it.
