Named stone
Van Horn quarry stones
Also called Van Horn butterscotch agate, Van Horn red felsite, Purple-tan chert (Van Horn)
A kind of chert (and flint)
Van Horn quarry stonesChert (and flint)Texas & SouthwestDescription
The country around Van Horn, in Culberson County, holds huge amounts of chert, agate and felsite, and prehistoric quarries named for what they produce. Archaeologists documented nine quarries. The Purple-Tan chert quarry has very dense, glossy chert that is mostly tan, purple only on the rind. The Spotted quarry has red and pale orange spotted chert. The Butterscotch quarry has brown agate that looks like butterscotch taffy. Three white chert quarries and three felsite quarries in dark reds also exist. At the Chispa Creek Folsom sites, most of the points and preforms were made of red felsite, butterscotch jasper and purple-tan chert, with only a few of Edwards chert from central Texas. Felsite served for heavier tools and the finer stones for points.
How to identify it
- Colour
- Purple-Tan chert: mostly tan, with grayish orange, very pale orange, grayish red-purple, pale red and pinkish gray; purple mainly on the outer rind. Spotted chert: moderate red to grayish red with very pale orange spots. Butterscotch agate: light brown, dark yellowish brown, moderate brown. White chert: white, medium light gray, pinkish gray. Felsite: dark reddish brown, dark red, moderate red, grayish red.
- Texture
- Purple-Tan chert: extremely dense, fine and glossy, with excellent conchoidal fracture and thin translucent flakes. Spotted chert: medium to fine grained, matte. White chert: coarse to fine grained. Felsite: coarse to fine grained, extremely hard and dense.
- Luster
- Glossy in the Purple-Tan chert; matte in the Spotted chert.
- Cortex
- The Purple-Tan chert has a purple outer rind that is normally knapped away.
Geology
Cretaceous limestone hills east of Van Horn hold nodules of Purple-Tan chert and white chert. Spotted chert caps a mesa in the Van Horn Mountains. Butterscotch agate comes from the Wylie Mountains (with similar stone at Needle Peak near Pinto Canyon). Felsite pebbles and boulders lie among pediment gravels in the Carrizo Mountains west of town, with fragments of agate, chalcedony and jasper.
Where it comes from
Texas & Southwest
States
Quarries and outcrops
- Purple-Tan chert quarry (41CU449)
- Spotted quarry (41CU389)
- Butterscotch quarry (41CU424), Wylie Mountains
- Three white chert quarries (41CU349, 41CU372, 41CU379)
- Three felsite quarries (41HZ397, 41CU441, 41CU443), Carrizo Mountains
- Chispa Creek sites, Lobo Valley, southern Culberson County
Used by
- Folsom: at the Chispa Creek sites, 82 of the Folsom points and preforms are of Van Horn red felsite, butterscotch jasper and purple-tan chert
- Used extensively throughout prehistoric times for all chipped-stone forms, with felsite for heavier tools and finer cherts and agates for points (Hedrick and others, as summarized by Texas Beyond History)
Look-alikes
Stones that are easy to confuse with Van Horn quarry stones.
- Edwards chert (the non-local stone in the Chispa Creek Folsom tools)
Sources
- Texas Beyond History (University of Texas at Austin, Texas Archeological Research Laboratory). Van Horn Quarries. Trans-Pecos section.texasbeyondhistory.net (opens in a new tab)
- Texas Beyond History (University of Texas at Austin, Texas Archeological Research Laboratory). Earliest Peoples of the Trans-Pecos (Chispa Creek).texasbeyondhistory.net (opens in a new tab)
