Chow Tai Fook's reply that "all rubies are heated" is obviously exaggerated. The red color of natural ruby is very stable, so it can be "fixed" without "heating". The blue topaz seen in the market is irradiated with colorless and transparent topaz to make it blue, and then fixed at low temperature, otherwise the blue will be unstable and fade gradually. This is different from the reason why natural rubies are red, and the two cannot be confused. It cannot be inferred that "rubies are all heated" because topaz is colored by irradiation and then fixed at low temperature. According to the interpretation of the national standard of jewelry and jade, there are strict restrictions on the optimal treatment of natural gemstones: common enhancement methods: heat treatment, bleaching, wax immersion, colorless oil immersion, etc. Common treatment methods: soaking in colored oil, filling treatment (glass filling, plastic filling or other hard materials such as polymers), soaking in wax (turquoise), dyeing treatment, irradiation treatment, laser drilling, film covering treatment, surface diffusion treatment, etc. There is a clear stipulation on the naming of jewellery and jade after optimized processing: you can directly use the "optimized" gemstone name without adding it in its appraisal certificate. Naming of "treated" gems: put brackets after the names of jewels and jade, and indicate the words "treated", such as "topaz (treated)". In its appraisal certificate, it is necessary to add notes to explain the specific treatment methods, such as "Remarks: Irradiation Treatment". Under the current general appraisal technical conditions, if it is uncertain whether it has been treated, the word "treated" may not be added after the name of jewelry and jade, but it must be added, and the following description methods are adopted, such as "topaz, remark: whether it has been irradiated" or "topaz, remark: it may have been irradiated". Therefore, if a ruby is "heated", it is only "optimized" and remains a natural gem. In the jewelry industry, processed jewelry and jade are generally no longer considered "natural". For rubies, special attention should be paid to whether they have been treated by surface diffusion, dyeing or filling.