
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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