Agates Inside Out
by Karen A. Brzys
Agates Inside Out
|
|
| Dedication |
vi
|
| Acknowledgements |
vii
|
| Introduction |
viii
|
| Chapter 1: What is an Agate? |
1
|
| A Basic Description |
1
|
| Agates and Human History |
2
|
| Agates and Their "First Cousins" |
4
|
| Macrocrystalline Quartz |
4
|
| Fibrous Microcrystalline Quartz |
8
|
| Granular Microcrystalline Quartz |
9
|
| Silicified Fossils |
10
|
| Quartz Properties |
14
|
| Chapter 2: How Did Agates Form? |
16
|
| The Earth - In the Beginning |
16
|
| Agate Formation |
21
|
| Inflow Agate Genesis Theory |
24
|
| Possible Sources of Silica |
28
|
| Silica Transport |
31
|
| Infiltration Channels |
34
|
| Concentric Banding |
41
|
| Horizontal Banding |
55
|
| Silica Gel Agate Genesis Theory |
57
|
| Agate Genesis Conclusions |
60
|
| Silica Gel Theory |
60
|
| Inflow Theory |
62
|
| Types of Host Rock |
65
|
| Igneous Rock Agates |
67
|
| Amygdaloidal Agates |
67
|
| Rhyolitic Agates |
70
|
| Sedimentary Rock Agates |
73
|
| Timing of Agate Formation |
76
|
| Chapter 3: How Do You Find Agates? |
82
|
| A Pocket Filled In |
88
|
| Banding and Other Patterns |
90
|
| Translucency |
93
|
| Color |
95
|
| Shape, Size, and Weight |
106
|
| Luster |
109
|
| Husk |
112
|
| Connective Channels |
118
|
| Pseudobands |
120
|
| Agate-Want-to-Be |
122
|
| Chert, Flint, and Jasper |
122
|
| Metamorphic Rocks |
126
|
| Secondary Fills |
127
|
| Silicified Fossils |
128
|
| Other Agates-Want-to-Be |
132
|
| Caring For and Cleaning Agates |
135
|
| Assessing the Value of Agates |
138
|
| Chapter 4: What Are the Different Types of Agate? |
139
|
| Botryoidal (Grape) Agates |
139
|
| Brecciated (Mosaic) Agates |
140
|
| Candy Striped Agates |
141
|
| Carnelian Agates |
142
|
| Cloud Agates |
144
|
| Crazy Lace Agates |
144
|
| Dendritic Agates |
146
|
| Enhydro (Water-Filled) Agates |
150
|
| Eye Agates |
151
|
| Fire Agates |
156
|
| Flame Agates |
158
|
| Floater Band Agates |
159
|
| Fortification Agates |
159
|
| Geode Agates |
161
|
| Iris (Rainbow) Agates |
162
|
| Jasper Agates |
165
|
| Moss Agates |
165
|
| Paintstone Agates |
168
|
| Peeler Agates |
168
|
| Plume Agates |
170
|
| Polyhedroid Agates |
172
|
| Pseudomorph Agates |
173
|
| Ruin Agates |
174
|
| Sagenite Agates |
175
|
| Sardonyx |
177
|
| Seam Agates |
178
|
| Shadow Agates |
180
|
| Stalk Aggregate Agates |
182
|
| Thunder Egg Agates |
182
|
| Tube Agates |
184
|
| Water-Level Agates |
186
|
| Chapter 5: Where Can You Find Agates? |
187
|
| A Selection of United States Agates |
187
|
| California |
190
|
| Florida |
191
|
| Idaho |
192
|
| Iowa |
193
|
| Kentucky |
194
|
| Michigan |
196
|
| Minnesota |
198
|
| Missouri |
200
|
| Montana |
201
|
| New Mexico |
203
|
| Oregon |
204
|
| South Dakota |
207
|
| Texas |
210
|
| Wyoming |
211
|
| A Selection of International Agates |
212
|
| Argentina |
212
|
| Australia |
215
|
| Botswana, Africa |
216
|
| Brazil |
218
|
| Canada |
220
|
| Caribbean |
223
|
| China |
225
|
| Mexico |
227
|
| References |
231
|
| Index |
239
|
| Museum Information |
243
|
| How to Vote for Your Favorite Photograph |
244
|
| Information About Agate DVDs and Other Products |
244
|
| Rock Hunting Log |
245
|
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