10. For gemstones smaller than 1 carat, "minute" is a common unit of weight in China. 1 carat equals 100 carat, 3 times 4 mm weight 10 carat, which is 0. 1 carat. Gem refers to the kind of stone or mineral inlay that can meet the requirements of jewelry after grinding and polishing. This precious ore is bright in color and high in hardness, and will not change under the action of atmosphere and chemicals.