Short answer
Zari is metallic thread, traditionally gold or silver coloured, woven or embroidered into sarees and fabrics to create borders and motifs. Surat has been a major centre of zari production for generations.
Historically, zari was made with real gold or silver wrapped around silk. Today most commercial zari uses metallised polyester or copper-based threads, which look rich at a much lower cost. Surat's old-city localities such as Gopipura and Saiyedpura are associated with the traditional zari trade.
When buying, check that zari threads lie flat, do not snag easily and keep their shine. Ask what type of zari is used, because it affects price and care.
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