NOTE I. (p. 215). Amount of Potash in Different Minerals. Felspars— | | | Percentage of potash. | (a) Orthoclase | {9.11 | 10.28 | 11.07 | 12.12 | 12.47 | | {13.49 | 14.35 | 15.21 | 16.7 | | (b)Oligoclase | 0.50 | | | | | (c)Labradorite | 0.33 | | | | | Mica | {5.61 | 6.20 | 7.23 | 8.26 | 8.95 | | {9.00 | 10.25 | 12.40 | 13.15 | | Amphibole | 0.25 | 2.96 | | | | Pyroxene | 0.34 | 2.48 | | | | Leucite | 13.60 | 18.61 | | | | Zeolites | 0.30 | 9.35 | 0.98 | 4.93 | | Stassfurt potash salts— | Per cent. | (a) Polyhallite, potassium sulphate | 28 | (b) Karnallite (KCl.MgCl26H20), potassium chloride | 24 to 27 | (c) Sylvin, pure potassium chloride. | | (d) Kainit (K2SO4MgSO4MgCl26H2O), potassium sulphate | 32 | (e) Schoenite (K2SO4, MgSO4, 6H2O), pure potassium magnesium sulphate. | | NOTE II. (p. 217). The quantity of potash obtainable from various plants in the manufacture of potashes on a large scale is illustrated by the following statements. 1000 lb. of the following vegetative products yield the following quantities of potashes:— | lb. | Old spruce-wood | 1/2 | Old poplar-wood | 3/4 | Old oak-wood | 1-1/2 | Corn-stalks | 17-1/2 | Bean-stalks | 20 | Grape-vine | 40 | (Storer, 'Agricultural Chemistry,' vol. ii. p. 108.) | |
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