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Plate I
A
Gem-quality celestite crystals from Travis County, Texas. Twice natural size. Lower portion of the crystals is colorless; the tips are dark blue.
B
Opalized wood from the Texas Gulf Coastal Plain. Specimen at left is rich brown and tan; specimen at right is fossil palm wood and is black, reddish brown, and white. One-third natural size.
Plate II
A
Gem-quality garnet crystals and faceted gem from Gillespie County, Texas. Natural size.
B
Labradorite from Brewster County, Texas. Both stones are pale yellow. One and a half times natural size.
Plate III
A
Pink microcline crystal from Burnet County, Texas.
B
Smoky quartz from Burnet County, Texas. Natural size. Colorless crystal at center back is included for color comparison.
Plate IV
Polished agate from gravels of the Rio Grande near Zapata, Zapata County, Texas. Bands are blue and gray; other inclusions are brown, yellow, and reddish. One and a half times natural size.
Plate V
A
Texas tektites (bediasites) showing variety of surface features. Natural size.
B
Topaz crystal from a pegmatite dike near Streeter, Mason County, Texas. Natural size. Measurements: 1½ by 1? by 3 inches; weight: 194 grams (970 carats); pale blue; mostly gem quality.
Plate VI
A
Topaz from stream gravels near Streeter, Mason County, Texas. Natural size. Left to right: colorless worn pebble; emerald-cut pale-blue topaz, weight 10 carats; pale-blue worn pebble, weight 205 carats; step out sky-blue topaz, weight 13 carats; pale-blue worn pebble.
B
Tourmaline crystals in schist from Llano County, Texas.
