State Minerals, Rocks and Gemstones: What Each State Officially Chose

Short answer: most US states have written a mineral, rock or gemstone into law, and the choices track local mining history more than mineralogy. Checked against statutes and state surveys: Colorado's mineral is rhodochrosite, Utah's gem is topaz, Washington's gem is petrified wood, New Hampshire picked smoky quartz, Oregon picked sunstone, and Maine named tourmaline its mineral. Several "minerals" are really rocks, and Kentucky rewrote its list in 2024 to fix exactly that.

Which states have official rocks, minerals and gems?

The table below covers 20 states whose designations could be confirmed from the statute text itself or from the state's own geological survey or records office. States that could not be checked against a primary source are left out rather than filled in from secondary lists. Where a source gives the year of adoption, it is shown.

Two details stand out from the statute text. Nevada does not name its mineral in a stand-alone section shown here, but NRS Chapter 235 describes the silver in the state tartan as representing "the official state mineral". And North Carolina's General Statutes Chapter 145 calls the emerald its "official State precious stone" rather than its gem, a reminder that every legislature wrote its own vocabulary.

Why are so many state "minerals" not actually minerals?

A mineral has a strict definition, and lawmakers have not always used it. The cleanest case is Kentucky. According to the National Conference of State Legislatures, Kentucky designated coal as its official state mineral in the late 1990s. Coal is organic and has no fixed composition or crystal structure, so it is a rock. The 2024 fix made coal the state rock, moved Kentucky agate to state gemstone because agate lacks a rigidly consistent chemistry, and picked calcite, the major component of limestone, as the new state mineral. Lawmakers also dropped the freshwater pearl as gemstone after finding it is more common in Tennessee than in Kentucky.

Utah handled the same material correctly from the start. The Utah Geological Survey lists coal as the state rock and spells out that rocks can be composed of solid organic matter, with coal as the example, while its mineral is native copper.

Other designations lean on trade names or on fossil material:

• Petrified wood. Washington's RCW 1.20.090 makes petrified wood the official gem, and Texas chose petrified palmwood as its stone. Neither is a mineral species: Geology.com's table of US gem production files fossilized wood under cryptocrystalline quartz, next to agate and jasper. The petrified wood guide covers how that replacement happens.
• Agatized coral. Florida's statute describes its state stone as "a chalcedony pseudomorph after coral", a precise phrase: the coral's shape survives while silica takes over the substance. The same process is explained in the pseudomorphs guide.
• Prairie agate. Nebraska's law calls it "the chalcedony stone, commonly known as prairie agate", then names it the state rock, even though the same Geology.com table lists chalcedony under cryptocrystalline quartz, a mineral.
• Thunderegg. Oregon declared the thunderegg its official rock in 1965, naming a collector's term rather than a rock type you would find in a petrology textbook.

None of this makes the choices wrong as symbols. It does mean a state list is not a mineralogy lesson, and buyers should not assume "state mineral" means a single mineral species. For the real taxonomy, see the mineral classes guide.

What do the choices say about each state's history?

Metals that built an economy

Utah's copper is a mining story. The Utah Geological Survey reports that the Bingham Canyon open pit in the Oquirrh Mountains has produced over 21 million tons of copper since open-pit operations began in 1906, and that the pit is now nearly 2.5 miles wide and over 0.5 miles deep. Missouri and Wisconsin both chose galena, which the Wisconsin statute identifies as lead sulfide. Missouri adopted it in 1967, the same year its law named mozarkite "the official rock and lithologic emblem of Missouri".

Maryland's choice is the newest in the table. The Maryland Department of Natural Resources explains that chromite, recognized as the state mineral in 2025, was discovered in Maryland by Isaac Tyson Jr. some time between 1808 and 1827. Tyson noticed it always occurred in serpentine, so the barren serpentine hills of Baltimore County led him to ore. For a period Maryland was the primary and sometimes sole source of chromite in post-colonial American industry.

Building stone

Granite is the most repeated choice in the table: New Hampshire, North Carolina and Vermont each name it, South Carolina names blue granite as its stone, and Wisconsin names red granite. Vermont went further than anyone, listing three state rocks (marble, granite and slate) alongside talc as its mineral, all quarry products.

Gems with a real local source

Some gem choices point to deposits a collector can visit. Utah's survey describes topaz in Beaver, Juab and Tooele Counties, forming from fluorine-bearing vapors during the last stages of cooling of siliceous igneous rocks. In the Thomas Range it sits in cavities in rhyolite, and its prized sherry-amber color alters to rose-pink or clear silver-white in sunlight, which matters if you plan to display a Utah crystal in a sunny window.

Oregon's sunstone is another. GIA describes Oregon sunstone as a transparent feldspar with glittery copper inclusions and notes it is gaining attention as a natural, untreated American product. Nevada's precious gemstone is not just "opal" but specifically Virgin Valley black fire opal, a single district. Montana's 1969 law names sapphire and Montana agate together.

Are state gems actually mined in their states?

Often not in quantity. Geology.com reports that thirteen states produce almost all of the natural gemstones mined in the United States: Arizona, Arkansas, California, Colorado, Idaho, Louisiana, Maine, Montana, Nevada, North Carolina, Oregon, Tennessee and Utah. Its table of USGS figures puts total US gem output at about 9.5 million dollars in 2014, with turquoise around 1.3 million dollars a year, which is small for a country this size.

That gap shows up in the statutes. Florida's stone law stresses that agatized coral is "indigenous to Florida", while its 1970 gem law simply describes moonstone as "a transparent or translucent feldspar of pearly or opaline luster" without tying it to a Florida deposit. Ohio's 1965 law adopts "Ohio Flint", described in the statute as a crypto-crystalline variety of quartz, as its gem stone, so even flint can carry a state's name. For the US deposits that actually supply today's market, from Arkansas quartz to Herkimer crystals, see the United States origins guide.

Shopping for state symbol stones we stock

A state symbol is a good theme for a small collection, but match the label to the stone, not to the state. Most of the polished material on the market is mined abroad even when the mineral is a US state symbol, so read the locality line in the listing and treat an unlabeled piece as unknown origin. For a theme collection, a rough specimen with a stated locality tells more of the story than a polished shape without one.

• Hessonite Garnet Cluster 2.6KG WA State, USA: a rare US-mined piece, about 8 by 6.5 inches on matrix from Washington. Minerals.net defines hessonite as the orange to orange-brown variety of grossular, the same garnet species Vermont named its state gem. More in the garnet guide.
• Smoky quartz sphere 60mm 260grams: New Hampshire's state gem in an affordable polished form; look for even brown color and inclusions you can see through the polish.
• Watermelon Tourmaline on Albite Matrix 51g: tourmaline is Maine's state mineral. This 52 gram piece is Brazilian, but it shows the pink and green color zoning that gives watermelon tourmaline its name, on a white albite base.
• Sunstone: Oregon's gemstone theme. Check the listing for locality; glittery copper inclusions point toward Oregon material, while unlabeled sunstone may come from elsewhere. The sunstone guide explains the differences.
• Petrified Wood Sphere: Washington's state gem and close kin to Texas petrified palmwood. These are from Indonesia, listed at about 20 million years old, so they suit a theme collection rather than a Washington locality set.

Frequently asked questions

Does every state have an official state mineral?

Not every state has all three. In the 20 states checked for this guide, Washington's law names a gem, Nebraska's a rock and Maine's a mineral, while Vermont's statute names a gem, a mineral and three rocks. Coverage varies because each legislature acts on its own.

Why did Kentucky change its state mineral?

Kentucky had named coal its state mineral in the late 1990s, but coal is organic and lacks a fixed composition, so geologists class it as a rock. In 2024 the legislature made coal the state rock, calcite the state mineral and Kentucky agate the state gemstone.

Which state rock is chosen most often?

Granite appears most often among the states checked here. New Hampshire, North Carolina and Vermont name granite, Wisconsin names red granite, and South Carolina names blue granite as its official stone. All reflect long quarrying histories.

Is petrified wood really a gemstone?

Washington law says so, and it has been the official state gem there since 1975. Geology.com groups fossilized wood with cryptocrystalline quartz such as agate and jasper, so it is better described as a fossil and a stone than as a single gem mineral.

Are state gemstones always found in that state?

Not always. Many are, such as Utah topaz, Oregon sunstone and Nevada's Virgin Valley opal. Others honor a material more than a deposit, and only about thirteen states produce nearly all US natural gemstones, according to Geology.com.

Sources

• National Conference of State Legislatures, Rocks 'n' Rules: https://www.ncsl.org/resources/details/rocks-n-rules
• Utah Geological Survey, Utah's State Symbols: https://geology.utah.gov/map-pub/survey-notes/glad-you-asked/state-symbols/
• Colorado Geological Survey, Symbols of Colorado: Mineral, Gem, Rock and Fossil poster: https://coloradogeologicalsurvey.org/publications/symbols-mineral-gem-rock-fossil-colorado-poster/
• Maryland Department of Natural Resources, Chromite State Mineral Recognition: https://news.maryland.gov/dnr/2025/06/27/chromite-state-mineral-recognition-alludes-to-marylands-past-as-the-chrome-capital-of-the-world/
• Oregon Legislature, ORS Chapter 186, State Emblems: https://www.oregonlegislature.gov/bills_laws/ors/ors186.html
• Washington State Legislature, RCW 1.20.090 State gem: https://app.leg.wa.gov/RCW/default.aspx?cite=1.20.090
• Nevada Legislature, NRS Chapter 235: https://www.leg.state.nv.us/NRS/NRS-235.html
• Missouri Revisor of Statutes, 10.047 State mineral: https://revisor.mo.gov/main/OneSection.aspx?section=10.047
• Missouri Revisor of Statutes, 10.045 State lithologic emblem: https://revisor.mo.gov/main/OneSection.aspx?section=10.045
• Wisconsin Legislature, Statutes 1.10: https://docs.legis.wisconsin.gov/statutes/statutes/1/10
• Maine Legislature, Title 1 Section 213 Official mineral: https://legislature.maine.gov/statutes/1/title1sec213.html
• New Hampshire General Court, RSA Chapter 3: https://www.gencourt.state.nh.us/rsa/html/I/3/3-mrg.htm
• Nebraska Legislature, Statute 90-110: https://nebraskalegislature.gov/laws/statutes.php?statute=90-110
• Florida Legislature, Statute 15.034 State gem: http://www.leg.state.fl.us/statutes/index.cfm?App_mode=Display_Statute&URL=0000-0099/0015/Sections/0015.034.html
• Florida Legislature, Statute 15.0336 State stone: http://www.leg.state.fl.us/statutes/index.cfm?App_mode=Display_Statute&URL=0000-0099/0015/Sections/0015.0336.html
• Montana Legislature, MCA 1-1-505 State gem stones: https://leg.mt.gov/bills/mca/title_0010/chapter_0010/part_0050/section_0050/0010-0010-0050-0050.html
• Ohio Laws, Revised Code 5.07: https://codes.ohio.gov/ohio-revised-code/section-5.07
• Texas State Library and Archives Commission, Texas State Symbols: https://www.tsl.texas.gov/ref/abouttx/symbols.html
• North Carolina General Assembly, General Statutes Chapter 145: https://www.ncleg.gov/EnactedLegislation/Statutes/HTML/ByChapter/Chapter_145.html
• Vermont Legislature, Title 1 Chapter 11: https://legislature.vermont.gov/statutes/fullchapter/01/011
• Delaware Code, Title 29 Chapter 3: https://delcode.delaware.gov/title29/c003/index.html
• South Carolina Legislature, Code Title 1 Chapter 1: https://www.scstatehouse.gov/code/t01c001.php
• Geology.com, Gemstones Mined in the United States: https://geology.com/gemstones/states/
• GIA, Sunstone: https://www.gia.edu/sunstone
• Minerals.net, Grossular: https://www.minerals.net/mineral/grossular.aspx