Advertisement

If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.

ENJOY UNLIMITED ACCES TO C&EN

Geochemistry

Chemistry In Pictures

Chemistry in Pictures: #Twinning

by Alexandra Taylor
March 29, 2019

A micrograph showing blue and yellow crystals in different orientations.
Credit: Bernardo Cesare

This micrograph shows plagioclase, a type of feldspar, with a field of view of 2.7 mm. The sample hails from Brazil, and Bernardo Cesare, a geoscientist at the University of Padua, obtained it from a company that sells marble and granite for countertops. The plagioclase shown here is twinned, which refers to crystals that share lattice points but have different orientations. The blue areas all have the same orientation, and the yellow areas have a different orientation. Twinned plagioclase is found in igneous and metamorphic rocks all over the world. “In geology the composition of plagioclase is extensively used to determine the pressure and temperature of rock formation,” Cesare explains. Plagioclase is also commonly used as a raw material in the ceramics industry.

Credit: Bernardo Cesare

Do science. Take pictures. Win money. Enter our photo contest here.

Related C&EN content:

Naica’s crystal cave captivates chemists

Nanocrystals give hematite rainbow flair

Collision with Mars-sized object could explain Earth’s unusual element ratio.

Article:

This article has been sent to the following recipient:

0 /1 FREE ARTICLES LEFT THIS MONTH Remaining
Chemistry matters. Join us to get the news you need.