Bling, in the rough

Julie Brown

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New York City gem dealer Benjamin Zucker ’62 has an eye for fine jewelry. But he has never considered submitting these nine uncut sapphires, each about an inch and a half long, to the lapidary. Zucker says he bought the sapphires—now on display at the Peabody Museum—in the mid-1970s "for their educational value." As a group, this spectrum in crystal shows the wide range of colors that traces of iron, titanium, and chromium can produce in sapphires.

Every sapphire is a variety of corundum, a form of aluminum oxide that crystallizes under tremendous heat and pressure. If, however, the corundum contains traces of chromium only, the result is called a ruby. Alternatively, if the heat and pressure aren't quite right for creating precious stones, the result is garden-variety aluminum oxide crystals. They make a very good sandpaper.