16-Across in Monday's puzzle read [Gas that comprises about 1% of air] for a five-letter answer. If you said ARGON, give yourself a high-five!
Elements abound in crosswords: In addition to ARGON, you'll also see copious amounts of NEON, IRON, and RADON (which is dangerous in real life, but not in a puzzle grid). LEAD also finds its way into many puzzles, though of course it can be clued in many ways besides as an element thanks to its status as a homonym.
These elemental names are commonly seen in crosswords because of their short length, abundance of common letters, and familiarity. MOLYBDENUM, PRASEODYMIUM, and PROTACTINIUM are all, I'm sure, wonderful elements, but their lengths and unfamiliarity keep them pretty much shut out of puzzles.
Trivia: What's the only three-letter element? You'll find it in plenty of crosswords; answer at the end of this article.
Some elements help constructors out in a pinch: if you've got a five-letter answer that starts with X, then XENON is one of your few choices. And a four-letter word starting with Z could easily become ZINC, since the options there are limited, too.
You might expect to see BORON in crosswords more often than you do. It's short, it's got good letters, and it's got a very low chemical number of 5, surrounded by familiar names like CARBON, HELIUM, and NITROGEN. And yet it's only appeared in the New York Times crossword 19 times in the Will Shortz Era (1993-present), the main reason being that it's tough to clue in an interesting way since it doesn't appear naturally on Earth without being combined with other elements. In fact, one of the Shortz-Era clues for it was simply [Chemical element]! So when constructing, puzzle writers might not go out of their way to put BORON in.
Speaking of constructing, have you found that 3-letter element yet? Hint: it's hidden somewhere in the word "constructing"! When you find it, tweet to #beastxword and we'll all know how science-y you are.
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