190 ■ SMITH— PARAGENESIS OF MINERALS. [Octobers, 



markably close agreement between pargasite from Pargas (Fin- 

 land), that from Calaveras Valley, California, and the artificial 

 amphibole made by Chrustschoff in chemical composition, orienta- 

 tion of the axes of elasticity and the pleochroism. Pargasite from 

 Finland is optically positive, while that from California is negative, 

 but that is a minor difference. Chemical analyses of pargasite 

 from California, pargasite from Finland, and the artificial amphi- 

 bole are given below on the table with the actinolite. 



Carinthine. — This variety is rather common in the medium 

 basic and acid rocks of the glaucophane series. It resembles par- 

 gasite, but is greenish rather than jet-black, and in thin sections the 

 colors are not so dark. It occurs chiefly in long prisms, without 

 terminal planes. The plane of the optical axes is the symmetry 

 plane, the optical angle is wide and the character of the double 

 refraction is negative. The extinction angle of C A c is slightly 

 smaller than in pargasite, varying from 14° to 17°. The pleo- 

 chroism is strong, a = yellowish, t) = light olive green, C = greenish 

 blue. This mineral is common in the altered diorite near Searsville 

 dam, Santa Clara County, in a similar rock three miles southwest 

 of Redwood, in a quartz-lawsonite-glaucophane schist near the 

 Schrader farm, two miles west of Redwood, in the eclogite of Oak 

 Ridge, Santa Clara County, in the basic glaucophane schists at the 

 Junction School House near Healdsburg, and in the glaucophane 

 gneiss of Melitta, near Santa Rosa. No analyses were made of the 

 mineral in these occurrences, but W. C. Blasdale^ has described a 

 similar variety in the glaucophane schists from near Berkeley. 

 Blasdale's mineral has the same optical properties as those given 

 above for carinthine, a = light green, t = yellow green, and C = 

 bluish green. The analysis published by Blasdale and quoted below 

 shows this mineral to be like the typical carinthine of the Alps, in its 

 having lower magnesia and higher soda than common actinolite 

 has. It is safe to say that the mineral described by Blasdale under 

 the name of actinolite is the variety carinthine, which should be 

 distinguished because of its association with glaucophane, both in 

 California and in the Alps. It is quite likely that carinthine grades 

 over into pargasite, but the two are rather distinct in their occur- 



^ Bull Dept. Geol. Univ. Calif., II., pp. 328-335. 



