black opal

American  

noun

Mineralogy.

1. a dark variety of opal having the characteristic opaline play of color.

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black opal British  

noun

1. any opal of a dark coloration, not necessarily black

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Example Sentences

She has rings for him to don at his opening, including a black opal that sparkles in the sun.

From Los Angeles Times

“Uncut Gems,” out Wednesday, stars Sandler as Howard Ratner, a jeweler in Manhattan’s Diamond District who tries to repay his gambling debts by auctioning off a long-sought-after rock from Ethiopia containing rare black opals.

From Washington Post

Inside the guts of a fish packed in ice, a precious, raw black opal embedded in rock is making its way to Howard.

From Seattle Times

KG, as they call him in the film, becomes obsessed with this black opal that's a centerpiece of the story.

From Salon

This turns out to be a huge black opal that soon ends up in Howard’s possession, though not for long.

From New York Times