The opening sentence makes it sound like scientists have discovered "semiconductors" for the first time - yet they were never mentioned in the article. I feel l

The opening sentence makes it sound like scientists have discovered "semiconductors" for the first time - yet they were never mentioned in the article. I feel like I would have gained a better understanding of samarium hexaboride's unexpected properties if the author had contrasted them with a concept that is conceptually (?) similar. > "In a deceptively drab black crystal, physicists have stumbled upon a baffling behavior, one that appears to blur the line between the properties of metals, in which electrons flow freely, and those of insulators, in which electrons are effectively stuck in place. The crystal exhibits hallmarks of both simultaneously."