Table T7. Summary of different principal alteration types, Site 1188.

	Green silica-clay		Bleaching		Silicification
Color in hand specimen:	Bluish green to green		White to light gray		Gray to greenish gray
Typical mineralogy:
Cristobalite	Abundant		Abundant		Rare
Quartz	Abundant		Abundant		Abundant
Anhydrite	Absent		Abundant		Absent
Illite	Abundant		Abundant		Abundant
Chlorite	Abundant		Rare		Absent (?)
Pyrophyllite	Rare		Abundant		Rare
Pyrite	Abundant		Abundant		Abundant
Magnetite	Rare		Absent		Locally common
Style:
Pervasive	Abundant		Rare		Abundant
Vein/stockwork	Absent		Abundant		Rare