Since I bought the first and most expensive olivine-iron meteorite, it has been out of control. I have bought many gemstones, stones and semi-finished gemstones, including ruby, sapphire, olivine, fluorite, topaz, diamond, crystal, garnet, tourmaline, sapphire, pointy crystal, nanhong, jadeite and agate. I've tried to polish and carve all these, which is quite fun. Diamonds are difficult to process, but they have the best luster. Topaz and ruby and sapphire have the most kinds of colors, while olive and pomegranate sharp crystals have the highest cost performance. Others are easy to polish, low in price and low in hardness.