corundum
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
Diamond defines a hardness of 10 and is actually about four times harder than corundum, which is 9.
From Textbooks • Jan. 1, 2017
The Bronco mane and eyeball were created from orange sapphires while the head features pave-set diamonds and custom-cut corundum blue stone.
From Washington Times • Jun. 12, 2016
This crystalline aluminum mineral is called corundum, and people have been wearing it with pride for thousands of years.
From Scientific American • Apr. 14, 2012
On the Mohs scale, which measures minerals’ hardness from 1 to 10, corundum ranks at 9.
From BusinessWeek • May 31, 2011
How to Point a Pencil.—Rub the pencil to a point in the groove of a corundum file.
