116 BULLETIN 118, UNITED STATES NATIONAL MUSEUM. 



LIST OF SPECIMENS. 

 UNITED STATES. 



Nevada. 



Cabochon, circular girdle; green and black, mottled; 31.425 carats; 18 by 7 



mm. Gift of Pacific Gem Company No. 1100 



Candelaria, Esmeralda County: 



Table; elliptical girdle; bright green with dark spots; 5.24 carats; 21 

 by 10 by 3 mm. Gift of Mack Weber No. 1099 



Utah. 

 Lucin, Boxelder County: 



Seventy-one stones, cabochon, elliptical and pear-shaped girdles; show- 

 ing variation from pale green to deep green, mottled with gray and 

 black; 25.19 to 1.6 carats; 29 by 20 b> 7 to 9 by 7 by 4 mm. (figs. 1-3, 



4, 6, pi. 12) No. 1104 



Six stones, cabochon, elliptical girdles; green mottled with gray and 

 white; 113.15 to 56.42 carats; 45 by 35 by 12 to 35 by 25 by 10 mm. 

 (figs. 7, 8, pi. 12) No. 1101 



VESUVIANITE. 



Variety. — Calif ornite. 



Composition. — A complex silicate. 



Crystallization. — Tetragonal; habit prismatic to columnar. 



Color. — May be yellow, brown, or yellow-green, depending on the 

 state of oxidation of the iron present; pleochroism faint. 



Luster. — Vitreous; translucent. 



Hardness. — 6.5; a fairly durable stone. 



Specific gravity. — 3.40 ±0.10. 



Optical properties.— -Mean refractive index, 1.72; double refraction 

 weak, 0.006; optically uniaxial, negative. 



Vesuvianite in general is distinguished by its optical properties; 

 californite, a deep green variety, resembles some forms of serpen- 

 tine and jade; from the former it is distinguished by its much greater 

 hardness, from the latter by the fact that it is softer, more crystal- 

 line, and has a distinctly higher index of refraction. It occurs in meta- 

 morphic rocks, chiefly in limestone. Is rarely cut as a precious stone, 

 but the variety californite is sometimes carved or cut into slabs for 

 ornamental purposes. 



LIST OP SPECIMENS. 



LOCALITY NOT RECORDED. 



Brilliant, circular girdle; green-yellow; 0.51 carats; 5 by 4 mm No. 570 



VESUVIANITE, variety CALIFORNITE. 



UNITED STATES. 



California. 

 Happy Camp, Siskiyou County: 



Thirty stones, cabochon, various girdles; green and cloudy white; total 

 weight, 174.825 carats; 28 by 10 to 8 by 4 mm No. 1542 



