NAME. 

 Chalk. 



REMARKS. 



USES. 



Calcium carbonate. 

 (.CaCo3) 



Resembles white clay or kaolin but! Used for making lime and cement, 

 does not have the clayey odor.'uses similar to calcite which see. 

 Crumbles easily in the fingers. , 



Other 



Ice. 



Hvdrogen and 

 Oxygen. (H^O> 



Tasteless when pure. The ice on Well known, 

 ponds may show prisms on melting. 



Gypsum. 



Hydrous calcium 



sulphate. 

 (Ca SO*. 2 H-'O) 



The transparent foliated kind is It is burned and ground up and then 

 called selenite. The fibrous kind known as Plaster-of-Paris. Used for mak- 

 satin spar, and the massive alabas- ing casts, moulds, finishing interior of 

 ter. Fig. 14. 'houses, as a fertilizer, .\labaster is used 



for carving. 



Kaolin or 

 Clay. 



Hyrdous aluminium 



silicate. 



(Al-'03. 2 Si02, 



2H20) 



Has a greasy feel. Strong argil- Used for making brick, tile, pottery, etc. 

 laceous odor when breathed ufMjn. Pure kaolin is used for porcelain. 

 (1) 



Mica. 



Black is 



Biotite. 



Zolorless or 



;ray one is 



Muscovite. 



Halite or 



Salt. 

 (Common) 



Galena 



Calcite. 



Bornite. 



Sphalerite. 

 Zinc blende) 

 :BIack-jack) 



Thalcopyrite. 

 •opper pyrites) 



Malachite. 



Complex potash, Biotite is brown by transmitted Muscovite is the mica that is commonly 



aluminium silicate, 'light. The cleavage plates are flex- used. Its uses are insulating material for 



Biotite has magnes-;ible and elastic. (2) electrical apparatus, in doors of stoves and 



ium and iron also. I furnaces, for spangles on wall paper and 



certain brocades, and frosting on Christ- 

 mas cards. 



Soditmi chloride. 

 (Xa CI) 



Lead sulphide 



(PbS) 



May contain silver. 



Calcium carbonate. 

 (CaCOS) 



Readily soluble in water. Saline^The uses are well known, 

 taste. (3) 



The high specific gravity and cubic, Lead is used for solders, pipe for plumb- 



cleavage make this mineral easy to 

 determine. Figures 3, 20 and 21 



ing, shot, and many other uses. When galena 

 contains sufficient silver it is mined for 

 that. It is then called argentiferous galena. 



The cleavage form and the hardness 

 make it easv to determine this min- 

 eral. (4) Figures 4, 6, 16 and 18. 



Copper, iron Readily tarnishes on exposure. Oc- 



sulphide. jcurs with quartz and chalcopyrite. 



(Cu5 Fe S4) Called Peacock ore. 



Zinc sulphide. 

 (ZnS.) 



Copper-iron 



sulphide. 



(Cu Fe S2) 



Copper carbonate. 

 (CuC03. Cu (OH)2) 



The resinous appearance and hard- 

 ness make this an easy mineral to 

 determine. Fig. 22. 



Its hardness and color make it easy 

 to distinguish from pyrite and 

 bornite. The black objects on the 

 crystals in Fig. 15 are chalcopyrite. 



Malcahite is often interbanded with 

 azurite, a blue copper mineral of 

 nearly same composition. May oc 

 cur as stalactites. 



Few minerals have so wide a variety of 

 uses as lime. .\ very few are given. They 

 are, in plasters and mortars, cement, etc. 

 The chemical uses are very numerous : 

 fertilizers, bleaching nowders, gas and 

 glass manufacture, etc. (4) 



.\n ore of copper. Contains 63.3% copper. 



The most common ore of zinc. 



.\ very common ore of copper. Contains 

 34.5'^ i^ of copper. 



.\ common ore of copper. Much prized 

 for gems, especially where interbanded with 

 azurite. 



Dolomite. 

 (Pearl spar) 



Calcium and magnes- 

 ium carbonate. 

 ((CaMg)C03) 



The crystal faces of this mineral 

 are always curved so the crystals 

 look like saddles. See Fig. 15. 



t 



Many of its uses are the same as for 

 calcite. Used as refractory material for 

 lining furnaces, etc.. for making Epsom 

 salts, and many others. 



I.imonite. 



Hydrous iron 



oxide. 



(2 Fe203. 3 H20) 



Usually has a fibrous structure. 

 When earthy it is brownish yellow 

 to ochre yellow. Very common 

 iron oxide. 



Used as an ore of iron. The earthy kinds 

 when ground are used for paint. 



Pyro.xene 

 .Augite. 



Calcium, magnesium, 



iron, aluminium 



silicate. 



(Complex) 



Usually short, thick prisms, which 

 are nearly square. Figures 9 & 11. 

 This mineral is common in some 

 igneous rocks and is hard to tell 

 from hornblende. 



This is a very common mineral in igneous 

 rocks. 



325 



