PREFACE

Materials ListLocal Gray Cherts (San Andres Formation ? west of Pecos river ?)1 light to medium gray, fairly homogeneous color (2)2 light and dark gray, shades contrasting but not banded (8)3 medium to dark gray (9)4 dark gray to black (6)5 fine-grained, solid medium gray (61)10 orange or reddish-gray (heat treated) (1)11 yellowish-gray (gray with yellow cast) (64)12 yellow and gray (indistinct zoning) (10)13 tan (17)18 fingerprint (or zebra) with well-defined alternating light and dark gray lines (7)19 light gray banded (4)23 red and gray (60)24 light and dark mottled reddish-gray (3)30 light to medium gray with white speckles (5)35 coarse gray or gray-brown (62)36 coarse gray "limey" (coarse-grained but nonsilicious or not shiny in appearance) (15)37 coarse fingerprint (or zebra; coarse variety of #7) (11)38 coarse gray with wide bands of very similar color (12)39 gray-brown with abundant dark brown, pen-point-size inclusions (Seven Rivers drainage ?) (68)40 dappled gray with white or light gray (occasional red) (Seven Rivers drainage ? or possibly Delawaremountains, TX, south of Carlsbad) (69)45 possible Rock House Canyon chert (65)59 undifferentiated gray (63)Other Cherts (possibly from west of Pecos river)60 brown (but not gray-brown) (16)61 dark brown (19)62 mottled light and dark brown (71)63 medium brown with white and black dapples (20)70 red and yellow (75)71 red, reddish-orange, red and yellow (73)75 white chalcedonic (70)76 white and brown chalcedonic (14)80 gray and black chalcedonic (76)89 white (burned to state of dehydration; often crazed) (18)Local Chalcedonies (presumed)90 clear to off-white (81)91 clear to off-white with brown areas (84)92 clear with solid white inclusions (83)100 white to yellowish-gray cherty (85)101 off-white with traces of brown-red inclusions (24)105 light yellow with white inclusions (80)106 light gray with black inclusions (23)107 light gray with light gray-brown cherty areas (28)6-39