The bottle on the table was a shade under half full. Dark brown, almost black, the contents appeared even darker. Poured ever so carefully into a small tasting glass, the mahogany-colored whisky released the salty scents of its birthplace by the sea. This was Black Bowmore, a treasure usually seen only at auctions, a legendary malt Scotch that had been distilled in 1964 on Islay, the fabled island off the west coast of Scotland.

The precious 42-year-old we tasted is only just now reaching U.S. shores. It has aged well, still giving off that distinctive cloud of sea air and smokiness, some sweetness on the palate and a warm, lingering aftertaste. The original sherry casks in the warehouse at Islay have been drained, and this will be the last time the ’64 will be available on the open market. There were three previous releases as the whisky matured, the first at age 29 in 1993 and then at 30 and 31 in successive years.

When this final batch arrives in the U.S. as numbered bottles, packed in polished wood boxes with copper-inlaid letters, alluding to the copper stills, it will have been more than a decade since the U.S. received an allotment. Scarce and sought after, rare bottles from previous releases now sell at multiples of twenty to sixty times their original price at auction.