The use of a stone or Jade Egg to strengthen the vagina is a practice that evolved in ancient China. As time went on, the secret of this practice remained in the Royal Palace and was taught only to the queen and concubines. Many who mastered the technique experienced very good health, remaining young and bountiful, with *ual organs in old age as tight and resilient as those of a young, unmarried lady. Some believe that the queen and concubines practiced the technique in order to please the king while making love.