Shocked Quartz
Shock metamorphism of rock structures in and around impact sites is one major way scientists use to identify them. Even small quartz grains of sand have fracture lines running through them created from the tremendous shock absorbed during impact as silica materials, both terrestrial and extraterrestrial, were destroyed. All types of biarre shapes were created and brecciation is common. Multiple fracture lines are quite visible even though some recrystallization of congenetic melt particles do appear, both as single pieces and in mass.
The Gulf of Mexico has been the main source of shocked quartz, impact glass and microtektites for many years. All of this material can only be considered as alluvial since it was deposited from the atmosphere during the event or carried into the ocean by erosion from the continent. Only the astrobleme itself can offer areas of pure debris dediment unaffected by contamination from other sources.
The many brilliant colorations found in this material are highly suggestive of a mesosiderite type chrondite asteroid.