This mode of operation is actually a means for jewelers to attract customers in the name of discount, and they can also sell high prices through this means.
The usual practice of these jewelers is to increase the marked price of low-grade goods by 10 to 20 times on the basis of the original price, and then make the so-called discount. Once someone is fooled into buying it, they can at least sell it at a price 50% higher than the original actual price. The general market price of this kind of gold inlaid jade mentioned in the question does not exceed that of 400 yuan.
Jewelry stores are generally better, especially in tourist areas, and the actual transaction price is generally too high. The so-called discount is actually much higher than the actual market price.
The correct way is: after getting this lottery ticket or seeing this discount promotion, ignore it, throw it away directly, and walk away without giving him a chance to fool.