ALIBATES FLINT (CHERT)
(Helpful links and additional information from members [JoshinMO], [chase] and [bigbudmma])
The Alibates Flint Quarries National Monument (formerly known as the Alibates Flint Quarries and Texas Panhandle Pueblo Culture National Monument) is located near Amarillo in Potter County, Texas. The area is now protected and can only be viewed on ranger-led guided tours, booked in advance.
For thousands of years, from Clovis times onwards, Native Americans exploited the rainbow-hued lithic material. There was extensive mining in later times by the Antelope Creek people of the Panhandle culture, between 1200 and 1450 AD, as evidenced by their stone-slab houses in the surrounding area. The material was also traded throughout the Great Plains and beyond.
The National Park Service website has a page on Alibates Flint here:
…and a “geology fieldnotes” page here:
The “Texas Beyond History” website from the University of Texas at Austin has a wealth of information about the Alibates Flint Quarries and their associated ruins here, together with pictures of artefacts made from the material:
Here’s a few examples of the material posted on the forum:
A broke from the Southern Colorado plains – picture by [bigbudmma]
A Southern Colorado birdpoint – picture by [bigbudmma]
A broken knife-scraper from Southern Colorado – picture by [bigbudmma]
Despite the official naming of the Alibates quarries as “flint quarries” the material found there is very much a chert. Geologically, it’s agatized dolomite and that’s what’s responsible for the distinctive marbling and banding that it exhibits.
Dolomite is a mineral. The “dolomite” from which Alibates chert formed is more properly known geologically as “dolostone”. It’s a magnesium rich limestone and qualifies for the term dolostone when the mineral content is more than 50% dolomite. At levels below that it’s called “magnesian limestone” or “dolomitic limestone” (sometimes also known in America as “cotton rock” because it’s rather light).
Forum member [chase] picked up these not-very-hard rock samples in the Texas panhandle, northeast of the quarrying area and wondered if they might be dolomite/dolostone:
The answer is probably “yes” since this is the kind of material that – after agatization – produced the layer of much harder material up to six feet thick that lies just below the surface in the quarrying area.
(Helpful links and additional information from members [JoshinMO], [chase] and [bigbudmma])
The Alibates Flint Quarries National Monument (formerly known as the Alibates Flint Quarries and Texas Panhandle Pueblo Culture National Monument) is located near Amarillo in Potter County, Texas. The area is now protected and can only be viewed on ranger-led guided tours, booked in advance.
For thousands of years, from Clovis times onwards, Native Americans exploited the rainbow-hued lithic material. There was extensive mining in later times by the Antelope Creek people of the Panhandle culture, between 1200 and 1450 AD, as evidenced by their stone-slab houses in the surrounding area. The material was also traded throughout the Great Plains and beyond.
The National Park Service website has a page on Alibates Flint here:
…and a “geology fieldnotes” page here:
The “Texas Beyond History” website from the University of Texas at Austin has a wealth of information about the Alibates Flint Quarries and their associated ruins here, together with pictures of artefacts made from the material:
Here’s a few examples of the material posted on the forum:
A broke from the Southern Colorado plains – picture by [bigbudmma]
A Southern Colorado birdpoint – picture by [bigbudmma]
A broken knife-scraper from Southern Colorado – picture by [bigbudmma]
Despite the official naming of the Alibates quarries as “flint quarries” the material found there is very much a chert. Geologically, it’s agatized dolomite and that’s what’s responsible for the distinctive marbling and banding that it exhibits.
Dolomite is a mineral. The “dolomite” from which Alibates chert formed is more properly known geologically as “dolostone”. It’s a magnesium rich limestone and qualifies for the term dolostone when the mineral content is more than 50% dolomite. At levels below that it’s called “magnesian limestone” or “dolomitic limestone” (sometimes also known in America as “cotton rock” because it’s rather light).
Forum member [chase] picked up these not-very-hard rock samples in the Texas panhandle, northeast of the quarrying area and wondered if they might be dolomite/dolostone:
The answer is probably “yes” since this is the kind of material that – after agatization – produced the layer of much harder material up to six feet thick that lies just below the surface in the quarrying area.
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