648 MINERALOGY 



Laurionite, PbCl(OH); White; H. 3-3.5; F. 1 ; IV; 

 Yields water. 



Nasonite, Pb 4 (Pb.Cl)2Ca 4 (Si 2 .07)3; White; H. 4; F. 2 ; 

 G. 5.42; II? 



In the closed tube yields a sublimate of lead iodide; 

 d, p. 589. 



Schwartzenbergite, Pb(I.Cl) 2 .2 PbO ; Honey- to straw- 

 yellow ; H. 2-2.5; G. 6.2; F. 1; III. 



7. The nitric acid solution shows phosphoric acid with ammo- 



nium molybdate ; p. 590. 



PYROMORPHITE, Pb 4 (Pb.Cl)(P0 4 )3 ; White, yellow, 

 brown, green; H. 3.5-4; G. 6.80 ; F. 2 ; III; p. 511. 



8. The mineral powdered and dissolved in nitric acid shows 



silica; 6, p. 591. 



a. Becomes magnetic in R. F. 



Melanotekite, (Fe 4 O 3 )Pb 3 (Si0 4 ) 3 ; Dark brown to black; 



H. 5-5.5; G. 5.85; F. 2; IV. 

 Hancockite, (Pb.Ca.Mn) 2 (Al.Fe.Mn.OH) (Al.Fe.Mn) 2 



(Si.CMs ; Brownish red ; H. 6.5-7 ; G. 4.03 ; F. 3 ; 



V ; Shows Mn with borax. 



b. With Turner's flux it yields a green flame (boric acid). 

 Hyalotekite, (Pb.Ca.Ba) 4 (F.OH)B(SiO 3 ) 6 ; White; H. 



5.5; G. 3.80; F. 3?; Massive. 



c. In the borax bead it shows manganese. 

 Kentrolite, (Mn 4 3 )Pb 3 (SiO 4 ) 3 ; Black; H. 5.5; G. 



6.19 ; F. 2-2.5 ; IV. 



Ganomalite, Pb 3 Si 2 7 (Ca.Mn) 2 SiO 4 ; Gray to white; 

 H. 3; G. 5.74; F. 3?; II. 



d. Silicate of lead only. 



Barysilite, Pb 3 Si 2 7 ; White ; Pearly ; Cl. basal ; H. 3 ; 

 G. 6.50; F. 2.5; III. 



9. Not included above. 



a. Show r s molybdenum; a, p. 586. 



WULFENITE, PbMo0 4 ; Yellow, orange, red, white; 



H. 4.5-5 ; G. 6.05 ; F. 2 ; II ; p. 545. 

 6. Shows vanadium ; b, p. 577. 



DESCLOIZITE, Pb(Pb.OH)VO 4 ; Brown, red; Resin- 

 ous; H. 3.5; G. 6.05; F. 1.5; IV; p. 514. 

 Brackenbuschite, Pb,Fe,Mn,(VO 4 ).H 2 O?; Dark-brown; 



F. 1.5; V. 

 c. Shows vanadium, 6, p. 577, and chlorine. 



