How to verify silk and zari authenticity?

I’m thinking of getting myself a Black Kanjivaram Saree for a wedding. The color is really impressive, but I would like to know how it can be styled. What would be the appropriate blouse, jewelry, and accessories to be used along with it? Do these sarees feel comfortable while wearing them for a prolonged period of time during a function? Finally, how does one check the authenticity of the silk and zari used in the sarees?
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