The Collaborative International Dictionary of English v.0.48:

Superfine \Su"per*fine\, a.
   1. Very fine, or most fine; being of surpassing fineness; of
      extra nice or fine quality; as, superfine cloth.
      [1913 Webster]

   2. Excessively fine; too nice; over particular; as, superfine
      distinctions; superfine tastes.
      [1913 Webster]

WordNet (r) 3.0 (2006):

superfine
    adj 1: of extremely fine size or texture; "superfine sugar"; "a
           superfine file"
    2: excessively delicate or refined [syn: overrefined,
       superfine]
    3: (used especially of merchandise) very fine in quality; "made
       of superfine Flemish cloth"

Moby Thesaurus II by Grady Ward, 1.0:

51 Moby Thesaurus words for "superfine":
   Babylonian, Corinthian, awe-inspiring, awful, barbaric, deluxe,
   divine, elaborate, elegant, exquisite, extravagant, fancy, fine,
   gilt-edged, glorious, golden, grand, grandiose, heavenly, immense,
   imposing, impressive, luxurious, magnificent, majestic, marvelous,
   noble, palatial, plush, posh, princely, proud, ritzy, sensational,
   splendacious, splendid, splendiferous, stately, sterling,
   sumptuous, super, superb, supereminent, superexcellent, superfancy,
   swank, swanky, swell, terrific, tremendous, wonderful