The gem cannot be polished without friction, nor man perfected without trials.
— Confucius

Improve your spare moments and they will become the brightest gems in your life.
Ralph Waldo Emerson gems quote

A gem cannot be polished without friction, nor a man perfected without trials.
— Chinese Proverbs

Proverbs are mental gems gathered in the diamond fields of the mind.
— William R. Alger

Candor is the brightest gem of criticism.
— gems quotation by Benjamin Disraeli