Name	Natural	Non-heat treated points	Heat treated points	Color details	Primary found in:	Associated Formation / Member
Alsen Chert				Mottled dark gray to a dark brownish gray.	New York, Maryland, New Jersey, Pennsylvania, Virginia, West Virginia, Vermont, Massachusetts, Connecticut	Alsen Cherty Limestone Formation of the Helderberg Group
Argillite (Generic type)				Light to dark green, but may range to various shades of gray.	North America	Varies
Braintree Hornfels				Varies from a medium to dark gray	Massachusetts, Connecticut	Braintree Argillite Formation
Briarcliff Chert				Light with darker patches.	New York, Pennsylvania, New Jersey, Massachusetts, Connecticut	Briarcliff Dolomite Formation of the Wappinger Group
Cheshire Quartzite AKA: Stissing Quartzite				Ranges from a white to a light gray or a tannish gray	New York, New Jersey, Connecticut, Rhode Island, Massachusetts, Vermont
Clough Quartzite				Ranges from white to a light pink.	Connecticut, Massachusetts, Vermont, New Hampshire	Clough Quartzite Formation
Coeymans Chert AKA: New Creek Chert				ranges in color from a bluish black to black.  Cloudy patches of fine pyrite and quartz may be present.	New York, Maryland, New Jersey, Pennsylvania, Virginia, West Virginia, Vermont, Massachusetts, Connecticut	Coeymans Limestone Formation (New Creek Formation), Helderberg Group
Crystal Quartz				clear colorless stone similar to clear glass	Eastern North America
Helderberg Chert				Ranges from mottled white to light cream, light gray, and light blue commonly mottled and fossiliferous.	New York, Maryland, New Jersey, Pennsylvania, Virginia, West Virginia, Vermont, Massachusetts, Connecticut	Helderberg Group
Kalkberg Chert				Ranges in color from a grayish blue to a black.  This chert is heavily cloudy by opaque patches.  Clastic quartz is present	New York, Maryland, New Jersey, Pennsylvania, Virginia, West Virginia, Vermont, Massachusetts, Connecticut	Kalkberg Formation of the Helderberg Group
Kittery Quartzite AKA: Cape Elizabeth Quartzite				Ranges from a light brown to light gray.	Massachusetts, Vermont, Connecticut, Rhode Island, Hew Hampshire, Maine, New York, and into New Jersey.	Kittery Formation of the Merrimack Group
New Haven Arkose				Ranges from a pink to red or gray indurated arkose.	Connecticut, Massachusetts, Rhode Island	Hew Haven Formation
New Scotland Chert AKA: Corriganville Chert, Minisink Chert				Ranges from a white to very light colors.	New York, Maryland, New Jersey, Pennsylvania, Virginia, West Virginia, Vermont, Massachusetts, Connecticut	New Scotland Formation (Corriganville Formation) of the Helderberg Group
Normanskill Chert AKA: Deepkill Chert, Coxsackie Chert				Range from a light green to a dark green or brownish green with darker bands being present.	Pennsylvania, New York, New Jersey, Connecticut, Massachusetts	Mount Merino and Indian River Formations of the Normanskill Group
Onondaga Chert AKA: See page				Vary from light to dark gray to a mottled bluish gray to a dark brown or black or tan.	Ontario, Quebec, New York, Pennsylvania, Jersey, Connecticut, Rhode Island, Massachusetts, Vermont	Onondaga Limestone Formation
Orthoquartzite (Generic type)				Varies	North America	Varies
Port Ewen Chert				Ranges in color from a dark gray to black	New York, Maryland, New Jersey, Pennsylvania, Virginia, West Virginia, Vermont, Massachusetts, Connecticut	Port Ewen Formation of the Helderberg Group
Quartz				Milky white with thin veins	North America
Quartzite				Varies from white to gray, or pink and tan in color	North America
Rhyolite				Gray to grayish black, flow banding may be present alternating from light to darker gray	North America
Westboro Quartzite AKA: See page				Ranges from a white to a light gray or light tan.	Rhode Island, Massachusetts, Connecticut	Albion Schist Formation