ruby glass

American  

noun

1. glass having a red color resulting from the addition of gold, copper, or selenium to the batch.

2. any glass of a dark red color.

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ruby glass British  

noun

1. glass that has a deep rich red colour produced from oxides of various minerals, such as lead, copper, and iron

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Etymology

Origin of ruby glass

First recorded in 1790–1800

Example Sentences

Though a fork and knife make one feel civilized while digging into the roast, this ruby glass of Rioja Alta doesn’t hurt.

From Salon • Nov. 8, 2025

Maybe human isn’t the best word to describe the characters, a race of mannequins made of ruby glass.

From The Verge • Feb. 25, 2016

Even without the guns, bullets, and ruby glass guys, Superhot would still be a pleasurable ballet simulator, with you dodging strings of red, in a fleet footed dance.

From The Verge • Feb. 25, 2016

Light flickered on bits of ruby glass and on sensitive capillary hairs in the nylon-brushed nostrils of the creature that quivered gently, gently, gently, its eight legs spidered under it on rubber-padded paws.

From "Fahrenheit 451" by Ray Bradbury

Red rays do not affect them; hence ruby glass is used in the "dark room."

From An Introduction to Chemical Science by Williams, Rufus Phillips