The conglomerate forms lenticular bodies, with clasts consisting mostly of Ortiz porphyry with small amounts of hornfels and chert.

Paleocurrents confirm deposition by stream flow from the Ortiz Mountains to the east.

[1] An ash bed about 200 meters (660 ft) below the top of the formation has a radiometric age of 11.65 ± 0.38 million years (Ma).

[1] The formation is interpreted as deposition by streams flowing from the east into a closed basin.

[5] They were designated as the Blackshare Formation of the Santa Fe Group by Connell et al. in 2002.