Metallic mineral deposits in Colfax and Union Counties, northeastern New Mexico
— Virginia T. McLemore and Robert M. North

The most important metallic mineral deposits in northeastern New Mexico are Great Plains Margin gold-silver deposits in the Elizabethtown-Baldy district. Similar deposits occur in the Cimarroncito district and possibly in the Laughlin Peak area. Thorium, yttrium and rare-earth veins with associated niobium also occur in the Laughlin Peak area and are related to intrusion of phonolite. Development of these deposits depends upon improvement of the markets for thorium, yttrium and rare-earth elements. Clastic plugs containing copper, silver and locally uranium occur in the Cimarron Valley and may be analogous to collapse-breccia pipes in northwestern Arizona. Other deposits occur in northeastern New Mexico, including sedimentary uranium, volcanic-epithermal gold, placer gold and stratabound, sedimentary copper deposits, but these deposits are small and probably uneconomic.