RED HILL

Collections from Sections 4 through 11,14,15,17 R19W, T2S USGS Red Hill 7.5' Quad, northwest Catron County, New Mexico.

Red Hill is, perhaps, one of the most petrologically unique obsidians in the Southwest. The nodules are found within a conglomerate that consists mainly of basalt cobbles, some quartzite and very little rhyolite (see also Findlow and Bolognese 1982:56). Findlow and Bolognese state that the obsidian extends "over much of Catron County" (1982:56). While the context is a Quaternary basalt, the obsidian is apparently related to earlier Tertiary silicic eruptions of the Mogollon-Datil Formation in the area (Elston et al. 1976; Willard and Weber 1958). Nodule densities are very low, usually less than 5 per 25 m². The largest nodule recovered was 8 cm in diameter, but most of nodules were 5 cm or less. Nodules up to 25 cm are reported by Findlow and Bolognese (1982:56; in 1995 after recent grading we recovered a number of nodules over 10 cm in diameter). Cortical material varies from a thin gray or brown to glassy. The aphyric glass ranges from a nearly transparent brown (like Superior) to a cloudy or banded light gray. The knapping quality is excellent, equal to any in the Southwest.

Bipolar reduction stations and isolated flakes commonly occur, but in very low densities commensurate with the low geologic density. A few biface preform fragments were recorded, all less than 5 cm in length. References are those noted above.

Raw elemental concentrations for Red Hill source standards. All measurements in parts per million (ppm).

`SAMPLE`	`Ti`	`Mn`	`Fe`	`Rb`	`Sr`	`Y`	`Zr`	`Nb`	`Ba`
`RH1`	`399.216`	`682.198`	`7335.155`	`183.413`	`14.465`	`40.646`	`72.174`	`48.491`	`50.189`
`RH2`	`352.889`	`803.516`	`7682.074`	`221.546`	`6.168`	`48.522`	`74.103`	`58.337`	`50.472`
`RH3`	`301.966`	`589.673`	`6522.008`	`163.745`	`12.109`	`33.826`	`66.560`	`48.280`	`51.659`
`RH4`	`417.113`	`819.549`	`8239.715`	`185.627`	`14.393`	`37.446`	`71.283`	`51.794`	`56.381`
`RH5`	`274.805`	`523.609`	`6020.387`	`173.914`	`5.247`	`41.119`	`66.595`	`58.796`	`43.410`
`RH6`	`396.882`	`594.963`	`6802.929`	`166.411`	`12.485`	`35.629`	`65.475`	`49.633`	`45.633`
`RH7`	`378.822`	`597.221`	`7010.369`	`175.738`	`12.047`	`39.720`	`67.964`	`47.868`	`49.744`
`RH8`	`365.092`	`445.194`	`5986.270`	`138.173`	`12.173`	`31.599`	`60.785`	`39.781`	`52.583`
`RH9`	`389.790`	`596.030`	`6709.028`	`170.710`	`12.100`	`37.148`	`68.047`	`50.525`	`49.196`
`RH10`	`390.695`	`614.299`	`7050.382`	`166.922`	`11.469`	`37.401`	`70.590`	`47.757`	`54.315`
`RH11`	`372.870`	`582.173`	`7023.465`	`163.415`	`11.593`	`34.955`	`67.916`	`46.702`	`50.983`
`RH12`	`340.184`	`609.308`	`6779.541`	`170.930`	`14.607`	`35.231`	`66.855`	`46.404`	`52.850`
`RHD`	`294.231`	`791.567`	`7443.382`	`215.930`	`8.581`	`45.694`	`74.368`	`65.714`	`50.274`
`RHE`	`377.244`	`586.849`	`6988.993`	`170.163`	`11.189`	`36.442`	`66.592`	`46.363`	`50.549`