Diamond has it! High cost performance. Diamonds are almost the same, depending on the grade and price of diamonds you choose. Now it is more popular to buy diamonds from online stores or customize them. Buying the same diamond in this brand store is 2 to 3 times more expensive than buying it in an online store. It is better to spend the same money to buy a bigger diamond in an online store. When you buy a diamond, people will not ask which brand you are at first, but how big the diamond you bought. Of course, the bigger the diamond, the stronger the value preservation. You can look at some websites, compare prices, and then make a decision. Recommend a few: diamond bird, platinum jewelry, Curran, etc. Go to their website and have a look! But if the landlord has money, you don't have to care about these. I hope I can help you.