51 
In the paint making industry gypsum is employed in the 
Manufacturing of “cold water paints,” in which it acts as the 
. or vehicle for the colour. It is also used to a lesser extent 
ln the making of paints, mixed in oils. It should be pure white, 
Ver y finely ground and free from grit. 
Finely ground gypsum, when spread upon the soil, has the 
Power of aiding in the decomposition of certain minerals and 
Us liberating plant-nourishing chemicals. It also plays a 
^ful part when mixed with manure which later is to be used as 
rtihzer. It is used, either in its crude state or mixed with 
ot-nourishing materials, to form certain artificial fertilizers, 
is ^ text ^ e i n d us try> very finely ground, white gypsum 
Use d to some extent as a filler for cotton goods. 
PREPARATION. 
in ^ ypsum * s usually won by open quarry methods, though 
is tl! me cases underground mining, similar to that of coal mining, 
Method employed. The material is hand cobbed to re- 
; . e an hydrite (anhydrous calcium sulphate) and other ob- 
,^ 10na ble materials. From the pits it goes to the mill, where 
crushed, and ground to the necessary degree of fineness. 
c ulou 6 *™ s k e d product is graded according to purity and 
Thf* 
{3 2Q . e Pnce of the uncalcined gypsum varies from $1.60 to 
ln Ontario and Quebec, while, in the west, the cost was 
Por ^cd as high as $7.50. 
ag m °unt of gypsum used in the manufacturing industries, 
cported by the consumers:— 
Locati 
ion 
Quebec* 16 Province s 
S n tarioV;;; 
B 25jSz*ia.:: 
No. of firms 
reporting 
consumption 
Domestic 
Imported 
Tons 
Tons 
3 
1600 
8 
293061$ 
180 
22 
30592f$ 
115 
6 
8825 
— 
1 
— 
3000 
40 
70324 
3295