Robert Christy, comp. Proverbs, Maxims and Phrases of All Ages. 1887.
Diamond
A barley corn is better than a diamond to a cock.
A diamond is not so precious as a tooth.Don Quixote.
A diamond is valuable though it lie on a dunghill.
A diamond with a flaw is preferable to a common stone without any imperfection.Chinese.
A fine diamond may be ill set.
Diamonds cut diamonds.
Diamonds dart their brightest lustre
From the palsy shaken head.Wordsworth.
If a diamond be thrown into the mire, it is a diamond still.Turkish.