Charles filter is a sharp tool to identify whether a gem is dyed or not. Not only jadeite, emerald and hetian jade dye leather, but also other gems can be identified under correct operation.
But it has its limitations. What should I do if the jadeite is only pickled and not dyed? Charles filter to determine whether it is a commodity, it will directly drop the chain.
Therefore, Charles filter is only a tool for understanding and dyeing identification of jewelry and jade, and it is a part of comprehensive testing. We need a variety of instruments such as refractive index, density, magnification inspection, spectrum, etc., and comprehensive data analysis to ensure that jade is true!