Tin: TRICLIXIC SYSTKM 



133 



Examples. There are no minerals crystallizing in the type, 

 hut several salts, as strontium bitartrate, Sr(C4H4O fl ) 2 . 5 H 2 O. 



Calcium thiosulphate, Ca^Oj . 6 H 2 O, Fig. 267, represents the 

 (.mil ination of (001) (010) (lIO) (Oil) (110) common on this >alt. 



The Crystalline Elements of the Triclinic System 



lut he triclinic system, where no elements are fixed, all five are 

 calculated from measured angles, as none of the axial angles can 

 be measured directly; at least five angles must be measured. 

 The angles generally chosen are the pinacoidal angles, 001 A 100; 

 001 A 010; 100 A 010, and the angles between the unit form and a 

 pinaroid, as 100*110; 001*101; 001 A 011. When any five of these 

 angles are measured, the axial ratios and axial angles may be 

 calculated. 



