CONTENTS
y
xh
CHAPTER IX
ORES oF Iron 7 . :
Iron—History and Qualities. Ore Supplies. Classification of
Iron-ores. Igneous Ores—Titaniferous Magnetites, Con-
tact Ores. Primary Lodes—Czecho-Slovakia and Westpha-
lia. Replacement Ores—Pyritic Masses, Oxide Ores. Bodies
due to Descending Solutions—Cumberland, Bilbao, Lake
Superior, Gellivaara, Adirondacks, and Mid Sweden. Ancient
Surface Sheets—Kiruna, Bedded Ironstones. Aqueous Pre-
cipitates. Blackband Ores. Bog Iron Ores. Surface Ores
—Efflorescent, Residual, and Alluvial Ores,
PAGE
129
CHAPTER X
Ores or MANGANESE AND CHROMIUM
Manganese Ores.
Chromium
CHAPTER XI
ORES oF ALUMINIUM, INCLUDING Bauxite
Aluminium—TUses and Separation. Bauxite.
, 2
PART III
EARTHY MINERALS
CHAPTER XII
THE Micas, ASBESTOS, AND GEMS . . . ’ , . 15%
The Micas—Distribution and Uses. Pneumatolytic Origin.
Mining Economics.
Asbestos. Monazite. The Gems—Diamond, South Africa,
Brazil; theories of formation based on supposed artificial
diamonds. Corundum group. Miscellaneous gems—Topaz,
Zircon, Jade, Lapis Lazuli, Garnets, Olivine, Opal.
CHAPTER XIII
Cray . . . 168
Essential Properties of Clay. China Clay—Pneumatolytic Origin,
German Deposits of various modes of formation. Fuller's
Earth.
CHAPTER XIV
BUILDING STONES AND ROAD METALS . 3 * . 175
Building Stones. Causes of Decay. Tests of Building Stones.
Microscopic Examination—Panama * Breaks.” Varieties of
Building Stones. Stone Preservation, Road Metals