The Lake Valley Limestone is a geologic formation widely exposed in southwestern New Mexico.

[3] The Andrecito and Alamogordo Members contain foraminifers characteristic of the Kinderhookian (lower Tournasian) while the foraminifers of the Tierra Blanca Member are Osagean (upper Tournasian to lower Visean).

[3] In 1941, Laudon and Bowsher removed the lowermost beds into the Caballero Formation and divided the Lake Valley Limestone into the Alamgordo, Arcente, and Dona Ana Members.

These had produced some 5.8 million ounces (180 tonnes) of silver by 1931, but the richest lode was worked out by 1883, and by 1960 the mines had closed.

The ore took the form of native silver, argentite, chlorargyrite, and bromargyrite, deposited in folds in impervious shale beds overlying intrusions of monzonite porphyry[5] of the Mogollon-Datil volcanic field.