What are the steps of jewelry processing into jewelry?
Friends who know, help answer, thank you!
Platinum diamond ring
My friend bought a platinum diamond ring and felt a bit light. I wonder if it was pitted? How to judge the authenticity of the platinum diamond ring?
Solar cell module wiring
Determine the wiring mode of the solar cell module according to the design drawing. The wiring mode of the solar cell module should meet the requirements of the design drawing. Wiring using multi - strand copper core wire, wiring should be the first to do tin treatment. Pay attention not to connect the positive and …