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Phaneritic Sedimentary Rocks (Coarse-Grained) Classification Chart			---	GRAIN SIZE
				1/256 to 1/16 mm (silt) Feels ever so slightly gritty, like the finest sandpaper	1/16 to 2 mm (sand) Feels and looks like medium to coarse sandpaper	> 2 mm (gravel)
MINERAL CONTENT				ROCK NAME
----- C O M P O S I T I O N -----	SCRATCHES GLASS (H>5.5)	Predominantly QUARTZ		SILTSTONE	QUARTZ ARENITE	QUARTZ PEBBLE CONGLOMERATE
		> 25% FELDSPAR < 75% QUARTZ			FELDSPATHIC WACKE (Arkose)	FELDSPATHIC (Arkosic) CONGLOMERATE
		MIXTURE of mineral fragments, rock fragments, and clay and silt			WACKE (Greywacke)	POLYMICT CONGLOMERATE
	DOES NOT SCRATCH GLASS (H<5.5)	CALCITE, variable color, H=3, REACTS VIGOROUSLY with HCl (effervesces)		FINE-GRAINED LIMESTONE	COARSE-GRAINED LIMESTONE calcite cleavage or large crystals evident FOSSILIFEROUS LIMESTONE contains visible fossils COQUINA porous, composed of shell fragments, looks like GRANOLA BAR OOLITIC LIMESTONE composed of sand-sized, spherical beads (ooids)
		DOLOMITE, variable color, H=3, REACTS with HCl, but RELUCTANTLY (may react only in powder form)		FINE-GRAINED DOLOSTONE	COARSE-GRAINED DOLOSTONE
		GYPSUM, WHITE but sometimes stained by hematite, H=2, NO reaction with HCl		GYPSUM EVAPORITE
		HALITE, COLORLESS and clear, or WHITE, H=2.5, TASTES SALTY		HALITE EVAPORITE

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