CLASSIFICATION OF METALS. 



133 



Barium, as sulphate 



Calcium, \ 



Strontium, I As carbonates, sulphates, silicates. 



Magnesium, 



Aluminum, in silicates. 



Iron, \ 



Zinc, [ As oxides, carbonates, sulphides. 



Cadmium, 



Arsenic, 



Antimony, 



Lead, I chiefly M su i p hides. 



Cobalt, 



Nickel, 



Molybdenum, J 



Chromium, ^ 



Manganese, > Chiefly as oxides. 



Tin, 



Classification of metals. 



Light metals. 



Sp. gr. from 0.6 to 4. 



Sulphides soluble in water. 



Light metals. 



Alkaline earth metals. 



Ba, Ca, Sr, (Mg). 



Oxides soluble ; 



Heavy metals. 



Sp gr. from 6 to 21.5. 



Sulphides insoluble in water 



Earth metals. 



Al, and many rare metals. 

 Oxides insoluble. 



Arsenic group. 

 As, Sb, Sn, Au, Pt, Mo. 



Carbonates insoluble. 



Heavy metals. 



Lead group. 

 Pb, Cu, Bi, Ag, Hg, Cd. 



Sulphides insoluble in dilute acids. 



Alkali-metal. 



K, Na, Li, (NHJ. 



Oxides, carbonates, and 



most salts soluble. 



Iron group. 



Fe, Co, Ni, Mn, Zn, Cr. 



Sulphides soluble in 



dilute acids. 



Sulphides soluble in am- 

 monium sulphide. 



Sulphides insoluble in 

 ammonium sulphide. 



Properties of metals. All metals have a peculiar lustre known 

 as metallic lustre, and all are good conductors of heat and electricity. 

 The color of most metals is white, grayish, or bluish-white, or dark- 

 gray ; a few metals show a distinct color, as, for instance, gold and 

 calcium (yellow), and copper (red). 



At ordinary temperatures metals are solids with the exception of 

 mercury, all are fusible, and some are so volatile tliat they may be 

 (Jistilled^ Most, probably all, metals may be obtained in a crystal- 

 lized condition. 



The combinations of metals among themselves are called alloys, or, 

 when mercury is one of the constituents, amalgams. These combina- 



