હીરાની પરીક્ષા ઝવેરી જ કરી જાણે

hīrānī parīkṣā jhavērī ja karī jāṇē

Literally: Only a jeweller knows how to test a diamond.
What it means: It takes one who knows the trade to tell what a thing is worth.

Gujarati Wikiquote · English is machine-made and nobody has checked it yet

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