Jade is a mineral. There are two kinds of jade: soft and hard. Usually, jade refers to nephrite. It belongs to one of the most common jewels. Nephrite refers to Hetian jade in a narrow sense, and broadly includes more than ten kinds of nephrite such as xiuyan jade, Nanyang jade and Jiuquan jade. Many nephrite have the same long history, such as xiuyan jade. Jade only refers to jade. Jade is a special mineral with sociality and treasure, which was screened and confirmed by the ancients in the process of making tools with selected stones for tens of thousands of years. Shuo Wen Jie Zi interprets jade as "the beauty of stone is jade". In Ci Hai, jade is simply defined as "a beautiful stone with moist luster". These statements are what we call jade in a broad sense today, including not only Hetian jade and jadeite, but also traditional jade such as chalcedony, xiuyan jade, Nanyang jade, crystal, agate, amber, coral, turquoise, lapis lazuli and Huanglong jade. Modern mineralogy divides jade into jadeite and nephrite. Jade is jadeite, while nephrite mainly refers to Hetian jade in Xinjiang, which is a narrow definition of "jade".