The Three Sacred Treasures of the Imperial Family refer to a mirror, a sword and a jewel that are believed to have been granted by Amaterasu Omikami (also known as Tensho daijin or the 'Sun Goddess') to her grandson Ninigi during 'Tensonkorin' when he descended from heaven to rule over the country.
三種の神器（みくさのかむだから、さんしゅのじんぎ）とは、天孫降臨の時に、天照大神から授けられたとする鏡・剣・玉を指す。