5-14
 The diagrams illustrate the relationship between the axial system
 and hand of twinned crystals.  The arrows indicate the hand.
Electrical
(Dauphine)
Combined
Optical
(Brazil)
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
-
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
Z
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
r
Twinning - Axial Relationships
T. L. Anderson, R. E. Newnham & L. E. Cross, "Coercive Stress for Ferrobielastic Twinning in Quartz," Proc. 31st Annual Symposium on Frequency Control, pp. 171-177, 1977, AD-A088221.

Processing Related Twinning References:

D. A. Cocuzzi & J. W. Laughner, “Effects of Surface Abrasion And Impurity Levels on Stress-induced Dauphine Twinning in Alpha Quartz,” Proc. 43rd Ann. Symp. On Frequency Control, Pp. 617-622, 1989.

E. P. EerNisse & R. W. Ward, “Quartz Resonator Sensors in Extreme Environments,” Proc. 45th Ann. Symp. on Frequency Control, pp. 254-260, 1991.

J.J. Boy & P.L. Guzzo, “Quartz Crystal Twinning Under Mechanical Stress: Experimental Measurements,” Proc. 1996 IEEE Frequency Control Symp., pp. 155-160, 1996.

T. Uno, “Temperature Compensation of Thickness Shear Mode Resonators Formed on Artificial Twinned Quartz Plates,” Proc. 1996 IEEE Frequency Control Symp., pp. 526-531, 1996.