In Burma they are used as a cure and preventative for appendicitis.

In Japan they cure boils and ulcers.

In Malaysia and Sumatra they are used to sharpen the kris, are considered very lucky objects, and have been credited with being touchstones for gold.

• Leach, Maria. “”Flint”.” Funk & Wagnalls Standard Dictionary of Folklore, Mythology, and Legend. 3rd ed. New York, New York: Funk and Wagnalls, 1972. Print.

A touchstone is a small tablet of dark stone such as slate or lydite, used for assaying precious metal alloys. It has a finely grained surface on which soft metals leave a visible trace. Drawing a line with gold on a touchstone will leave a visible trace. Because different alloys of gold have different colours (see gold), the unknown sample can be compared to samples of known purity. This method has been used since ancient times. 

• “Touchstone”. Oxford English Dictionary. Retrieved 10 March 2013.