And deep-brain'd sonnets that did amplify
Each stone's dear nature, worth and quality.
The diamond,--why, 'twas beautiful and hard,
Whereto his invised[8] properties did tend;
The deep-green emerald, in whose fresh regard
Weak sights their sickly radiance do amend;
The heaven-hued sapphire and the opal blend
With objects manifold: each several stone,
With wit well blazon'd, smiled or made some moan.


[Footnote 8: Rare word, only known in this passage. Century Dictionary
gives "invisible", "unseen", "uninspected", noting that some
commentators suggest "inspected", "tried", "investigated".]

Had Shakespeare felt much interest in the lore of gems, he had before
him most of the then available material in a book of which he seems to
have made some use.[9] This was an English rendering of the "De
Proprietatibus Rerum" of Bartholomæus Anglicus (fl. ca. 1350), by
Stephan Batman, or Bateman (d. 1587), an English divine and poet, who
in the later years of his life was chaplain and librarian to the
famous Archbishop Parker, and thus had free access to the latter's
fine library. His rendering, published in 1582, bears the following
quaint title: "Batman uppon Bartholome his Book De Proprietatibus
Rerum"; it was published in 1582, and appears to have been widely read
in England among those still interested in the learning of the
scholastic period. A much earlier English version, made by John of
Trevisa in 1396, was published by Wynkyn de Worde in 1495, and is
considered to be the finest production of his press.[10]