Tennessee State Rock, Mineral & Gem: Limestone, Agate, Tennessee River pearl

Tennessee's state rock is limestone, adopted in 1979. Tennessee's state mineral is agate, adopted in 2009. Tennessee's state gem is Tennessee River pearl, adopted in 1979. Tennessee's state fossil is Pterotrigonia (Scabrotrigonia) thoracica, adopted in 1998.

Symbol names and dates are taken from primary state sources linked below. Informal or proposed symbols are not listed unless adopted.

Limestone specimen — Limestone (not necessarily from Tennessee). Photo: Mike Davis, CC0, via Wikimedia Commons

State rock: Limestone

Adopted:: 1979
Law:: Public Chapter 42 (1979)

Limestone is a sedimentary rock with a Mohs hardness of about 3–4 and a dull luster, usually white, gray or brown.

How to identify limestone →

Often confused with: Carbonatite, Chalk, Coquina

Also an official symbol of: Indiana, Kansas

Agate specimen — Agate (not necessarily from Tennessee). Photo: James St. John, CC BY 2.0, via Wikimedia Commons

State mineral: Agate

Adopted:: 2009

Agate is a mineral (SiO₂) with a Mohs hardness of 6.5–7 and a waxy to vitreous luster, usually red, orange, white, gray, brown or blue.

Agate was first designated in 1969; in 2009 it was redesignated as the state mineral.

How to identify agate →

Often confused with: Blue Lace Agate, Carnelian, Chalcedony

Also an official symbol of: Kentucky, Louisiana, Maryland, Minnesota, Montana, Nebraska, South Dakota

Pearl specimen — Pearl (not necessarily from Tennessee). Photo: MASAYUKI KATO, CC BY-SA 3.0, via Wikimedia Commons

State gem: Tennessee River pearl

Adopted:: 1979
Law:: Public Chapter 192 (1979)
Variety:: freshwater pearl from Tennessee rivers

It is a variety of pearl. Pearl is a mineraloid with a Mohs hardness of 2.5–4.5 and a pearly luster, usually white, pink, black or golden.

How to identify pearl →

Often confused with: Aragonite

State fossil: Pterotrigonia (Scabrotrigonia) thoracica

Adopted:: 1998
Law:: House Joint Resolution 552 (1998)

Tennessee state symbols FAQ

What is the state rock of Tennessee?

Tennessee's state rock is limestone, adopted in 1979 (Public Chapter 42 (1979)).

What is the state mineral of Tennessee?

Tennessee's state mineral is agate, adopted in 2009.

What is the state gem of Tennessee?

Tennessee's state gem is Tennessee River pearl, adopted in 1979 (Public Chapter 192 (1979)).

What is the state fossil of Tennessee?

Tennessee's state fossil is Pterotrigonia (Scabrotrigonia) thoracica, adopted in 1998 (House Joint Resolution 552 (1998)).

Sources

We cite primary sources (statutes, state government pages, federal regulations, and land-manager sites). Third-party listicles are not used as citations.

Geologic Map & State Symbols — Tennessee Department of Environment and Conservation, Tennessee Geological Survey (accessed 2026-10-24).

Last verified 2026-10-24. Corrections welcome: if a statute has changed, tell us and we'll re-verify.

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