breislakiteMin.|ˈbraɪsləkaɪt| Also -ackite. [after Breislak, an Italian geologist of German descent.] A woolly-looking variety of pyroxene. 1869Phillips Vesuv. x. 296 Hornblende, or Amphibole, including Breislakite—in ejected blocks and scoriæ on Somma and Vesuvius.