Rockhound State Park is a

state park State parks are parks or other protected areas managed at the sub-national level within those nations which use "state" as a political subdivision. State parks are typically established by a state to preserve a location on account of its natural ...

New Mexico ) , population_demonym = New Mexican ( es, Neomexicano, Neomejicano, Nuevo Mexicano) , seat = Santa Fe , LargestCity = Albuquerque , LargestMetro = Tiguex , OfficialLang = None , Languages = English, Spanish ( New Mexican), Navajo, Ker ...

, United States, located southeast of Deming. It is named for the abundance of minerals in the area, and visitors can search for

quartz Quartz is a hard, crystalline mineral composed of silica (silicon dioxide). The atoms are linked in a continuous framework of SiO4 silicon-oxygen tetrahedra, with each oxygen being shared between two tetrahedra, giving an overall chemical form ...

crystals,

geode A geode (; ) is a geological secondary formation within sedimentary and volcanic rocks. Geodes are hollow, vaguely spherical rocks, in which masses of mineral matter (which may include crystals) are secluded. The crystals are formed by the fill ...

jasper Jasper, an aggregate of microgranular quartz and/or cryptocrystalline chalcedony and other mineral phases,Kostov, R. I. 2010. Review on the mineralogical systematics of jasper and related rocks. – Archaeometry Workshop, 7, 3, 209-213PDF/ref> ...

perlite Perlite is an amorphous volcanic glass that has a relatively high water content, typically formed by the hydration of obsidian. It occurs naturally and has the unusual property of greatly expanding when heated sufficiently. It is an industrial m ...

, and many other minerals. When the park opened in 1966, it was the first park in the United States to allow collection of rocks and minerals for personal use. The park consists of two units. The main park is located in the Little Florida Mountains and includes camping areas. The Spring Canyon Recreation Area is located to the southwest in the northern

Florida Mountains The Florida Mountains are a small long, mountain range in New Mexico. The mountains lie in southern Luna County about southeast of Deming, and north of the state of Chihuahua, Mexico; the range lies in the north of the Chihuahuan Desert regi ...

and is open only for day use.

Geology

Both units of the park are located in areas of

Tertiary Tertiary ( ) is a widely used but obsolete term for the geologic period from 66 million to 2.6 million years ago. The period began with the demise of the non-avian dinosaurs in the Cretaceous–Paleogene extinction event, at the start ...

volcanic rock. The Little Florida Mountains, where the main unit is located, was covered with

volcanic ash Volcanic ash consists of fragments of rock, mineral crystals, and volcanic glass, created during volcano, volcanic eruptions and measuring less than 2 mm (0.079 inches) in diameter. The term volcanic ash is also often loosely used t ...

around 33.5 million years ago. This may be Oak Creek Tuff erupted from the Juniper caldera in the

Animas Mountains The Animas Mountains are a small mountain range in Hidalgo County, within the " Boot-Heel" region of far southwestern New Mexico, in the United States. They extend north–south for about 30 miles (50 km) along the Continental Divide,Since ...

to the west. Other vents, now impossible to find, erupted

andesite Andesite () is a volcanic rock of intermediate composition. In a general sense, it is the intermediate type between silica-poor basalt and silica-rich rhyolite. It is fine-grained (aphanitic) to porphyritic in texture, and is composed predomi ...

over the tuff 28.5 million years ago. These rock beds, and associated beds of

fanglomerate Conglomerate () is a clastic sedimentary rock that is composed of a substantial fraction of rounded to subangular gravel-size clasts. A conglomerate typically contains a matrix of finer-grained sediments, such as sand, silt, or clay, which fill ...

(coarse debris eroded from the volcanic rock), were intruded by small volumes of

rhyolite Rhyolite ( ) is the most silica-rich of volcanic rocks. It is generally glassy or fine-grained (aphanitic) in texture, but may be porphyritic, containing larger mineral crystals (phenocrysts) in an otherwise fine-grained groundmass. The mineral ...

between 26 and 24 million years ago. Though volcanism was brief and limited,

hydrothermal circulation Hydrothermal circulation in its most general sense is the circulation of hot water (Ancient Greek ὕδωρ, ''water'',Liddell, H.G. & Scott, R. (1940). ''A Greek-English Lexicon. revised and augmented throughout by Sir Henry Stuart Jones. with th ...

continued for a long time after the eruptions, producing mineral veins,

geodes A geode (; ) is a geological secondary formation within sedimentary and volcanic rocks. Geodes are hollow, vaguely spherical rocks, in which masses of mineral matter (which may include crystals) are secluded. The crystals are formed by the fill ...

, " thunder eggs", and other interesting and valuable mineral resources. The area was mined for precious metals, copper, lead,

manganese Manganese is a chemical element with the symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron. Manganese is a transition metal with a multifaceted array of industrial alloy use ...

, and

fluorite Fluorite (also called fluorspar) is the mineral form of calcium fluoride, CaF2. It belongs to the halide minerals. It crystallizes in isometric cubic habit, although octahedral and more complex isometric forms are not uncommon. The Mohs sca ...

from about 1880 to 1956.

Gallery

File:Looking out over the non-electric site camping area, day use area, and visitors center at Rockhound State Park in Deming, New Mexico. Dragon Ridge is visible in the background.jpg, Looking out over the non-electric site camping area, day use area, and visitors center. Dragon Ridge is visible in the background File:Kallstroemia grandiflora spreads out across a hillside at Rockhound State Park in Deming, New Mexico.jpg, Kallstroemia grandiflora spreads out across a hillside at Rockhound State Park

References

{{authority control Geology museums in New Mexico State parks of New Mexico Parks in Luna County, New Mexico Protected areas established in 1965