There is a story of Phra Ruang who has supernatural words scattering the remaining rice from the meal on the ground, then he prayed for the rice to continue to live down to posterity. The rice became a magical mineral that sinking into the rocks, found at some mountains behind the city of Sukhothai as Khao Phra Bat Yai. Villagers called it " Khao Toke Phra Ruang." It was believed that it was sacred by the power of Phra Ruang and usually kept in houses for propitiousness and fortunes to owners. It could also be rubbed as a treatment for insect bites.
However, scientifically, Khao Toke Phra Ruang is a type of mineral formed in the metamorphic rock layer containing an oxide of iron; therefore, its color is black and a bit rusty. The mineral crystal is conglomerated c were cube. The mountains behind the city of Sukhothai are full of metamorphic rocks, this mineral. The Sukhothai people used wisdom to cut and polish Khao Toke Phra Ruang until it became dark gray and strangely beautiful. It is commonly used to make a sacred item. Those who are interested should not miss Khao Toke Phra Ruang, which is close to Ban Na intersection and the shop Sali Khao Tok Phra Ruang. There are not only many kinds of rice that you can choose from, but you can also enjoy the cutting and polishing process and listen to be interest stories from those who have explored Khao Toke Phra Ruang.