The number on a jade bracelet usually represents the weight unit of jade. Emerald is a kind of gem, and its quality is usually measured in carats, not grams. One carat equals 0.2 gram.

So, if you see a number on the jade bracelet, such as "10", it may mean that the jade weighs 10 carat, which is 2 grams. The quality of jadeite is usually related to its value and scarcity. The larger the carat, the more precious and expensive the jadeite is. Please note that the exact explanation may vary from region to region and culture, so if you want exact information, you'd better consult a professional jewelry appraiser or merchant.