borrowed from German (in compound Zinkblende), derivative of blenden "to blind, dazzle," going back to Old High German blentan, going back to West Germanic *blandjan, weak verb derivative corresponding to *blanda- "to mix, mingle," probably originally "to make murky, unclear" (see blend entry 1), whence also Old English blendan "to blind," Old Frisian blenda, Middle Dutch blenden
Note:
The mineral was so called because its lustrous crystals "dazzled" German miners into thinking it was galena, with which it often occurred, though smelting it produced neither lead nor zinc. See also etymology note at sphalerite.
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