Chapter D

Daingerfield: 70
Dallas: 88
Damon Mound salt dome: 91
daughter elements: 95, 96
Davis Mountains: 45, 85, 98
Delaware Mountains: 65
diamond: 62
diatomaceous earth: 78
diatomite: 40, 78
Dickens County: 79, 98
Dietrich, John W.: vii
dikes: 72, 79
dog-tooth spar: 46, 47
dolomite: 29, 30, 32, 36, 38, 40, 43, 54, 68, 75, 87, 88
dolomitic limestone: 68
Double Mountain Fork of the Brazos River: 43
double refraction: 46
dravite: 95
Duval County: 78, 83, 91, 97
dynamic metamorphism: 14

E
Eagle Flat: 93
Eagle Mountains: 56, 57, 90, 95
earth’s crust: 2
east Texas: 70
Ector County: 79
Edwards Limestone: 68, 69, 84
effervescence in acid: 18
El Capitan Peak: 1
elements: 7, 8, 95, 96
Ellenburger strata: 55, 84
El Paso: 48, 58, 85, 88
El Paso County: 48, 58, 62
epoch: 2
era: 2
erosion: 11
extrusive igneous rocks, definition of: 9

F
Fairland: 54
Falfurrias: 64
Fannett salt dome: 91
Fayette County: 52, 64, 84, 98
feldspar: 8, 29, 30, 31, 33, 34, 35, 37, 45, 51, 55, 59, 61, 72,
79, 80, 85, 86
albite: 55
amazonstone: 56
microline: 55, 56, 61
orthoclase: 55, 61
fibrous gypsum: 64, 65
filtering sand: 86
Fisher County: 20, 49, 58, 65
Flawn, Peter T.: vii
flint: 84
flowstone: 18
flow structure: 85
fluorite: 29, 32, 34, 35, 37, 38, 56, 72
Foard County: 52, 58
foliation: 87
fool’s gold: 53, 80
formation: 6
Fort Bend County: 91
Fort Worth: 88
fracture of minerals: 17
fragmental rocks: 12
Franklin Mountains: 48, 58, 62, 85
Frasch method of sulfur mining: 91, 92
Fredonia: 67
Freer: 78, 83
furnace (_see_ blast furnace; open-hearth furnace)

G
gabbro: 87
gneiss: 59
Gaines County: 83
galena: 17, 26, 57, 89, 90
argentiferous: 57, 90
Galveston County: 91
Gamble prospect: 67
gamma rays: 96
garnet: 31, 33, 34, 37, 58, 85, 87
Garza County: 97
Geiger counter: 96
gemstones: 56, 58, 77, 82, 94, 95
geode: 19, 46, 49, 82
geologic map: 4, 5
geologic time scale: 2, 3
geologists: 2
geology: 2
Gillespie County: 44, 45, 55, 58, 59, 60, 61, 65, 76, 80, 82, 83,
87, 88, 94
glass, natural: 9, 77, 85, 97
glass sand: 85-86
glauconite: 70, 73
glossary: 102-103
gneiss: 13, 41, 55, 56, 59, 67, 72, 73, 74, 76, 81, 87, 93, 97
conglomerate: 59
gabbro: 59
granite: 59
hornblende: 59
mica: 59
goethite: 70
gold: 26, 51, 59, 80, 90
fool’s: 53, 80
Gonzales County: 52, 84, 97
Grand Saline salt dome: 66
granite: 2, 8, 9, 13, 41, 48, 55, 56, 59, 61, 72, 76, 79, 81, 85,
87, 94, 95
gneiss: 59
opaline: 72
Granite Mountain: 62
Granite Shoals Lake: 56
granules: 85
graphite: 26, 27, 62, 75
schist: 63, 87
gravel: 12, 41, 91
green copper carbonate: 53
greensands: 70
Grit: 94
grossularite: 58
group: 6
Guadalupe Mountains, Peak: 1
Gulf Coast: 91
Gulf Coastal Plain: 20, 42, 43, 46, 51, 52, 58, 60, 65, 66, 78,
83, 84, 86, 87, 92, 97, 98
Gulf salt dome: 91
Gyp Hill salt dome: 64
gypsite: 65
gypsum: 28, 29, 30, 32, 36, 37, 43, 63, 70, 85, 91
alabaster: 65
fibrous gypsum: 64, 65
rock gypsum: 40, 65
rosettes: 63, 64
satin spar: 64
selenite: 63, 64, 76

H
halite: 28, 32, 34, 35, 36, 38, 40, 43, 65, 91
hand lens: 22
Hardeman County: 52, 58, 64, 65
hardness of minerals: 16, 99
Harris, Bill M.: vii
Harris, John S.: vii
Harris County: 65, 66
Hartley County: 79
Hays County: 45
Hazel Formation: 52
Hazel mine: 52, 53, 90
Heath mine: 60
hematite: 26, 27, 36, 66, 75, 84, 86
specular: 67
Henderson County: 70
High Island salt dome: 91
High Plains: 42, 46, 51, 65, 66, 78, 79, 83, 87, 97, 98
Hockley salt dome: 65, 66
hollandite: 26, 27, 28, 73, 74
Honey Creek area: 87
hornblende: 8, 59, 61
gneiss: 59
schist: 87
horn silver: 90
Hoskins Mound salt dome: 91
Houston: 70
Howard County: 45, 60
Hudspeth County: 45, 52, 53, 55, 56, 57, 58, 59, 60, 62, 65, 66,
67, 75, 79, 82, 83, 90, 93, 95
Humphreys, Alan: vii
Hutchinson County: 66
hyalite: 78
hydrochloric acid (_see also_ chemical tests): 18, 22