"Extinction angles on the (001) faces of the lime-soda feldspars." -Johannsen, 1908

Extinction Angles

"Extinction angles on the (001) faces of the lime-soda feldspars." -Johannsen, 1908

"Extinction angles on the (010) faces of the lime-soda feldspars." -Johannsen, 1908

Extinction Angles

"Extinction angles on the (010) faces of the lime-soda feldspars." -Johannsen, 1908