unprizable

un- +‎ prizable

unprizable (comparative more unprizable, superlative most unprizable)

1. (obsolete) Not prized or valued; without value; not worth capturing.
   • c. 1601–1602, William Shakespeare, “Twelfe Night, or VVhat You VVill”, in Mr. William Shakespeares Comedies, Histories, & Tragedies […] (First Folio), London: […] Isaac Iaggard, and Ed[ward] Blount, published 1623, OCLC 606515358, [Act V, scene i]:

     A bawbling vessel was he captain of,
     For shallow draught and bulk unprizable;

2. (obsolete) Invaluable; whose value is beyond estimation.
   • 1625, Nicholas Breton, Characters and Essayes, Aberdeen: Edward Raban, “A Quyet Woman,” p. 45,

     Shee is a Pearle, that is vnprizable;

   • 1725, Henry Baker, “The Petition” in Original Poems: Serious and Humourous, London, for the author, p. 2,

     If in all your boundless Store

     A Blessing so unprizable there be,

     Crown whate’er you gave before

     With a true Friend, full of Sincerity:

• unprizable in Webster’s Revised Unabridged Dictionary, G. & C. Merriam, 1913