David Hall:
Of the 10,008 Hawaiian commemorative half dollars originally struck (8 for assay and 10,000 for distribution), 50 were struck as matte proofs. These are true proofs with much sharper detail than on the regular strikes. However, the matte surfaces are an aquired taste and many collectors at the time of issue did not like the subdued appearances of these special strikes.
Today, it's estimated that all 50 of the original matte proofs survive. Many of these survivors are in lower proof grades, i.e. PR61 to PR63. PR64s and PR65s are rare and highly prized by sophisticated commemorative collectors.