וְהַמָּ֕ן כִּזְרַע־גַּ֖ד ה֑וּא וְעֵינ֖וֹ כְּעֵ֥ין הַבְּדֹֽלַח׃
Now the manna was like coriander seed, and the appearance thereof as the appearance of bdellium.
Read Jewish philosophical commentary on Numbers 11:7: and classical philosophical sources.