Geological State Symbols of the US


Here is a listing of the statesymbols that are related to geology or paleontology for each of the 50 states. They will be added in alphabetical order as I get to them.




                                                                    Year Established
State Rock: Marble                                        1969
State Mineral: Hematite                                 1967
State Gemstone: Star Blue Quartz                  1990
State Fossil: Basilosaurus cetoides                 1984

State Rock: Marble

Marble is a metamorphic rock that forms from limestone. It is mainly composed of calcite or dolomite but will often have other minerals as well (i.e. quartz, talc, forsterite, tremolite, etc.). It is often found to be primarily white with swirls of darker colors (black or brown) but can be almost any color of the rainbow depending on the impurities. The primary source of marble in Alabama is in Talladega County and it is referred to as the Sylacauga marble. This marble has been quarried and used in art and building stones throughout Alabama and the US.





State Mineral: Hematite

File:Vulcan statue Birmingham AL 2008 snow.jpgHematite is a mineral often referred to as rust. It is produced from the oxidation of iron and forms iron oxide in the form of Fe2O3. It is also one of the most common sources of iron ore and is often referred to as red iron ore. The hematite in Alabama was primarily mined from the Red Mountain Formation until 1975, where it became cheaper to import it. But at one time it was the states most developed non-fuel mineral industry, helping to build up Birmingham as an industrial center. In the 135 years hematite was mined, they produced ~375 million tons of ore. Birmingham is also known for the largest cast-iron structure ever made, the stature of Vulcan (picture right), produced entirely with Birmingham iron ore.



State Gemstone: Star Blue Quartz

star blue quartzQuartz is one of the most common minerals on Earth, primarily due to its simple structure and chemical formula, SiO2. Not to mention it is harder than most other common minerals. Quartz can come in almost any color, which is caused by impurities in the crystals, and has a variety of names including amethyst (purple quartz), smokey quartz (grey), etc. The special thing about Alabama's "Star blue quartz" is that it often contains little bits of amphibole (another type of mineral) and displays asterism (a star pattern in the light) when polished.

Although the state website claims that star blue quartz is common, it does not appear to be so. There are very few pictures of this specific variety of quartz, although blue quartz by itself is rather abundant.


State Fossil: Basilosaurus cetoides

Basilosaurus cetoides was a prehistoric whale that lived during the Cenozoic era, about 35 million Basilosaurus is a member of the whale family first discovered in Alabama in 1834. It was originally thought to be a swimming reptile but was later discovered that it was indeed a whale from the Eocene period. This whale also had hindlimbs that were mostly nonfunctional (it is theorized they could have been used during sex). The hindlimbs are likely a vestigial "organ" from the evolution of land animals to modern whales. Basilosaurus is most abundant in Alabama and has been found in Clarke, Choctaw, and Washington counties.










                                                                                               Year Established
State Mineral: Gold                                                                      1968
State Gemstone: Jade                                                                    1968
State Fossil: Woolly Mammoth (Mammuthus primigenius)               1986

State Mineral: Gold

picture of Gold Dust Image

Gold is a mineral made up entirely by the element Au (gold). It is bright yellow and very dense and malleable. Currently gold is considered one of the mot valuable metals on Earth, being used as the standard for most money (gold standard). Gold has an important history in Alaska. Originally when the territory was purchased it was referred to as a folly because this big hunk of land couldn't be worth anything. That was before gold was discovered. It began in the 1870's and continued through most of the 1900's. The beginnings of many communities in Alaska got their start as gold mining towns. Today Alaska is more known for it's oil exploration but gold still holds a prominent place in it's heart with Fairbanks remaining as a major gold exploration area.

State Gemstone: Jade


Jade is the pure gemstone variety of nephrite which is a metamorphic mineral in the tremolite family. Alaska has large deposits of jade throughout the state but its principle claim to fame is an entire mountain made out of Jade. The mountain is located far from any road, north of the Arctic Circle, near Kobuk, AK. Very large blocks have been taken out of the mountain and used to create statues including a 3,600 lb block for a police memorial statue. Currently, jade statues and jewelry produced from Alaska's famed Jade Mountain can be found all over the world, including a plaque embedded in the Washington Monument.



State Fossil: Woolly Mammoth


Dwarf Mammoth

The Woolly Mammoth, also known as Mammuthus primigenius, is a species closely related to modern day elephants which was covered with hair. Unlike most of the state fossils, mammoths are often found as complete specimens. They are usually frozen in the snow or buried in a swamp of Arctic regions. Most of the 100 or so remains of fully preserved mammoths have been found in Russia and Alaska. Mammoth remains are found throughout the northern reaches of the state as well as scattered throughout other regions. The local prehistoric people were known to have  had interactions with the mammoths. Evidence includes tools that were created from their tusks.

A small island off the coast of Alaska is also one of the last remaining locations where woolly mammoths lived (until ~3,750 BC). Since the island was small the mammoths that have been found here were dwarf varieties of the typical continental mammoths (pictured right).





                                                                                        Year Established

State Gemstone: Turquoise                                                    1974

State Fossil: Petrified Wood (Araucarioxylon arizonicum)        1988

Arizona appears to have several unofficial state minerals (copper and/or fire agate) but I will only talk about the official ones.

State Gemstone: Turquoise



Turquoise is a blue to green mineral made up of copper, aluminum, and hydrous phosphate (CuAl6(PO4)4(OH)). Turquoise has long been considered a valuable gemstone and is one of the oldest known gemstones. It is formed by the flowing of groundwater through copper deposits and so is often associated with copper in arid (desert) environments. In Arizona, almost all turquoise deposits are associated with copper mines and are usually mined in association with the copper or leased out to other companies by the copper mine. It is known that the Native Americans (the Anasazi and the Hohokam) mined the turquoise in Arizona to use in jewelery and for trade. Arizona is also home to one of the largest domestic turquoise mines in Kingman.




State Fossil: Petrified Wood (Araucarioxylon arizonicum)  


Petrified Wood"Petrified" in this instance does not refer to scared (although I'm sure it has been used that way in the past), the term "Petrified Wood" can refer to any type of tree that has been mineralized (turned into stone), the specific species of petrified wood (Araucarioxylon arizonicum) is an extinct conifer that is found throughout Arizona and New Mexico. There is a problem with the state fossil though, the original name of the species was based on three different species. This means that although one of the three was correct, two had to be renamed, resulting in several of the trees identified since the initial 1889 description were also likely named incorrectly. Proper identification can only be made with thin sections and close analysis so that is not likely going to happen for a majority of the samples, at least not any time soon. Arizona is host to one of the largest assemblages of petrified logs found partially in Petrified Forest National Park (~10% of all the petrified wood in northeastern Arizona). The concentrations of logs in PFNP are a result of log jams that flowed down rivers. The woody material was then replaced by silica (quartz) by silica rich waters flowing through the logs.
















                                                                                        Year Established

State Mineral: Quartz Crystal                                             1967

State Rocks: Bauxite                                                          1967

State Gemstone: Diamond                                                  1967


State Mineral: Quartz Crystal 


QuartzQuartz is one of the most abundant minerals in the crust of the Earth and easily one of the simplest minerals. It's chemical composition is SiO2 (silicon dioxide) and is a 7 on the Mohs Hardness Scale. Not only is it stable on the Earth's surface, it's harness means that it hangs around for a long time. This is the reason that the vast majority of sand is composed of quartz.

Quartz can be found in many different colors from purple (amethyst), to grey (smokey quartz), to white (milky quartz) but Quartz Crystal is often referred to the clear variety that has a crystal habit (pictured right), although any color of quartz can occur in a crystal habit. Quartz does not have any cleavage, meaning that when it breaks it doesn't form along perfect surfaces. Instead the Quartz Crystals grow, often by hydrothermal waters that are rich in dissolved silicon dioxide. As the waters flow over the crystals the silicon dioxide is deposited on the surface of the crystal, kind of like a stalactite in a cave.

Arkansas is known for the town of Hot Springs which has these hydrothermally heated pools flowing to the surface. These hydrothermal waters have produced some of the finest varieties of Quartz Crystals on the planet. There are many "dig your own quartz crystal" mines located in the areas around Hot Springs in the Ouachita Mountains, which allow people to dig for these crystals themselves. The Ouachita Mountains was considered to be a mystical location by the Native Americans and the Quartz Crystals were believed to have a sacred and spiritual significance, which is a belief of many holistic practitioners today.


State Rock: Bauxite


BauxiteUnlike quartz and diamond, bauxite is by far the least known of the three Arkansas state symbols. Bauxite well known for being the primary ore of aluminum, of which the majority of the aluminum in the world is from bauxite. The primary minerals of bauxite are gibbsite (Al(OH)3), boehmite (AlO(OH)), and diaspore (AlO(OH)). To extract the aluminum, the bauxite is crushed into a powder and the aluminum is leached out via several chemical procedures.

The obvious use of aluminum is as a metal, but it can also be used for abrasives (one of the byproducts of the leaching process has a hardness of 9), in cements, and as proppants (discussed below). Currently the United States is not even in the top ten for bauxite producers and it is only produced in a handful of localities in the United States (Arkansas, Georgia, and Alabama). But that was not always the case. In Arkansas bauxite first saw production in 1899, and increased in production until 1923 when Arkansas produced half of the world's supply at 500,000 tons that year. The peak of production was in 1943 when 6,000,000 long tons were produced but it has had a steady decline ever since. Currently the Arkansas bauxite is mined for production of proppants, which are high density spherical grains used by the oil and gas industry in fracking.

State Gemstone: Diamond


Uncle Sam DiamondOne of the most famous gemstones, the diamond also is one of the hardest minerals on earth (it is actually the third hardest after two extremely rare minerals called Wurtzite Boron Nitride and Lonsdaleite ( Made up entirely of carbon, like its cousin graphite (also made up entirely of carbon), the arrangement of the carbon atoms and the strength of the bonds are what give the two minerals completely different properties. Diamonds are most often found in structures called kimberlites or lamproites. Kimberlites are magmatic rocks that are formed deep within the Earth's surface. The high pressure converts the carbon into diamonds and the structures make their way to the surface as buoyant globs of rock. Due to being formed at such high pressure, diamonds are inherently unstable on the Earth's surface, however they degrade at such a slow rate that it isn't much of an issue to jewelry.


Several kimberlites/lamproites are known in Arkansas, with the largest being located in Crater of Diamonds State Park, where visitors are allowed to mine for diamonds and keep what they find. The largest diamond found in Arkansas is called "The Uncle Sam" which was 40.42 carats before it was cut and was discovered in 1924 (figured right).