હીરા આવ્યો હાથ, અજાણ્યા ઓળખે નહીં;

hīrā āvyō hātha, ajāṇyā ōḷakhē nahīṁ;

Literally: A diamond came into the hand, but the ignorant one does not recognize it;
What it means: Foolish people do not appreciate the value of precious things or opportunities when they get them.

Also said as

ગુજરાતી કહેવતસંગ્રહ (Gujarati Kahevat Sangrah) (1923) · read from the scan by machine — the Gujarati itself is unchecked · English is machine-made and nobody has checked it yet

Heard it differently, or know we've got the sense wrong? Tell us — that is exactly the kind of correction this needs.