Related pyro industries in an area likely tap the same sources of sand, calcium, soda, potash and other minerals. Which often have tell-tale trace element components that reveal their source.

The fluorite crystals in the turquoise cloisonne glass enamel is of interest, as fluorspar has a long history of use in Chinese ceramics.

Per Wikipedia:
Major fluorspar deposits are located in South Africa, Mexico, China and Mongolia. Historically, the mineral was used in ceramics manufacture as a fluxing agent, helping the enamel stick to porcelain in the firing process. ... The mineral itself is known as fluorite, its chemical symbol is CaF2, calcium fluoride.