This is how our brothers and future Portuguese fellow citizens call granite rocks from which small pieces in the shape of a biconvex disc are detached by thermoclastia and cryoclastia. This geological phenomenon is observed in Castanheira north of Braga and in some places in China. Stones that give birth or better those that are given birth are symbols of fertility for some women who put them under the pillow. It is now forbidden to take them.
