RocksdayNorth Dakota State Rock: Knife River flint
North Dakota's state rock is Knife River flint, adopted in 2025. North Dakota's state fossil is teredo petrified wood.
Symbol names and dates are taken from primary state sources linked below. Informal or proposed symbols are not listed unless adopted.
State rock: Knife River flint
- Adopted:
- 2025
- Law:
- N.D.C.C. 54-02-21; HB 1186 (2025)
- Variety:
- Knife River flint
It is a variety of flint. Flint is a sedimentary rock with a Mohs hardness of about 6.5–7 and a waxy luster, usually black, gray or brown.
State fossil: Teredo petrified wood
- Law:
- N.D.C.C. 54-02-08
- Variety:
- teredo-bored petrified wood
It is a kind of petrified wood. Petrified wood is a fossil with a Mohs hardness of about 6.5–7 and a waxy to vitreous luster, usually brown, red, yellow, gray or black.
How to identify petrified wood →
Often confused with: Chert, Jasper, Turritella Agate
Also an official symbol of: Arizona, Mississippi, Texas, Washington
North Dakota state symbols FAQ
What is the state rock of North Dakota?
North Dakota's state rock is Knife River flint, adopted in 2025 (N.D.C.C. 54-02-21; HB 1186 (2025)).
What is the state fossil of North Dakota?
North Dakota's state fossil is teredo petrified wood (N.D.C.C. 54-02-08).
Sources
We cite primary sources (statutes, state government pages, federal regulations, and land-manager sites). Third-party listicles are not used as citations.
- North Dakota Century Code chapter 54-02 (54-02-08 state fossil, 54-02-21 state rock) — North Dakota Legislative Branch (accessed 2026-10-24).
- HB 1186 (2025), designating Knife River flint as the state rock — North Dakota Legislative Branch (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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