Tianjin is one of the jewelry processing centers in China, and there are many factories that can process agate. Different manufacturers may charge different processing fees, but they are generally determined according to the following factors:

1. Material cost: Processing plants usually consider the cost of purchasing raw materials, including agate and other materials used in processing.

2. Complexity of processing technology: Different processing technologies may require different technology and time investment. For example, agate is carved and polished or embedded in other materials, and the complexity of these processes will affect the processing cost.

3. Processing quantity and specifications: If a large number of agates need to be processed, there will generally be a certain batch discount. In addition, processing agates of different sizes and shapes may require different working hours and technical input, and the price will be different.

4. Design requirements: If you have special design requirements, such as customized styles, personalized fonts or special shapes, these may involve additional design costs.

Because the structure of each processing plant is different, the charging method may be different. Therefore, I suggest you consult several factories when choosing a processing factory and compare their quotations and service quality.