First, look at the size. As the old saying goes, there are seven pearls and eight treasures. The bigger, the more valuable. Second, look at the luster, good pearls will be very shiny, and strong light is better (you can see yourself when you pick them up). The third is to look at flaws. You can't make high-grade jewelry with what you can see with the naked eye. If you hold a magnifying glass, you can't see it. Very rare. But natural things are inevitably flawed, so if you focus on "big and bright light is flawless", it is basically high-end. Of course, there is another factor that cannot be ignored, and that is color. Usually gold and black are rare, and natural things are rare. The famous Zhu Jin in Nanyang and the black pearl in Tahiti make the pendant very attractive. Generally, there are jewelry counters in high-end shopping malls. This is the usual standard. In fact, consumers still have their own standards, especially for accessories. They pay attention to an "eye-catching" and value the eyes most. After all, we buy jewelry to make ourselves happy, right?