Gemstone irradiation produce mixtures of blue and yellow-to-brown colors, so heating is required as an additional procedure to remove the yellowish color. In some cases, the new colors induced by artificial irradiation may fade rapidly when exposed to light or gentle heat, so some laboratories submit them to a "fade test" to determine color stability. Sometimes colorless or pink beryls become deep blue upon irradiation, which are called Maxixe-type beryl. However, the color easily fades when exposed to heat or light, so it has no practical jewelry application. Gemstone irradiation The gemstone irradiation is a process in which a gemstone is artificially
Varieties of Chinese Varieties of Chinese Chinese, also known as Sinitic, is a branch of the Sino-Tibetan language family consisting of hundreds of local language varieties, many of which are not mutually intelligible. The differences are similar to those within the Romance languages, with variation particularly strong in the more mountainous southeast. These varieties, often called "dialects", have been classified into seven to ten groups, the largest being Mandarin (e.g. Beijing dialect), Wu (e.g. Shanghainese), Min (e.g. Hokkien), and Yue (e.g. Cantonese). Chinese varieties differ most in their phonology, and to a lesser extent in vocabulary and syntax. Southern varieties tend to have