RocksdayMinnesota State Gem: Lake Superior agate
Minnesota's state gemstone is Lake Superior agate, adopted in 1969. Minnesota's state fossil is the giant beaver (Castoroides ohioensis), adopted in 2025.
Symbol names and dates are taken from primary state sources linked below. Informal or proposed symbols are not listed unless adopted.
State gemstone: Lake Superior agate
- Adopted:
- 1969
- Law:
- Minn. Stat. § 1.147
- Variety:
- Lake Superior agate
It is a variety of agate. 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.
Often confused with: Blue Lace Agate, Carnelian, Chalcedony
Also an official symbol of: Kentucky, Louisiana, Maryland, Montana, Nebraska, South Dakota, Tennessee
State fossil: Giant beaver (Castoroides ohioensis)
- Adopted:
- 2025
- Law:
- Minn. Stat. § 1.1466; 2025 c 39 art 2 s 1
The statute also gives its Dakota and Ojibwe names, capa and amik.
Minnesota state symbols FAQ
What is the state gemstone of Minnesota?
Minnesota's state gemstone is Lake Superior agate, adopted in 1969 (Minn. Stat. § 1.147).
What is the state fossil of Minnesota?
Minnesota's state fossil is the giant beaver (Castoroides ohioensis), adopted in 2025 (Minn. Stat. § 1.1466; 2025 c 39 art 2 s 1).
Sources
We cite primary sources (statutes, state government pages, federal regulations, and land-manager sites). Third-party listicles are not used as citations.
- Minnesota Statutes § 1.147, State gemstone — Minnesota Office of the Revisor of Statutes (accessed 2026-10-23).
- Minnesota Statutes § 1.1466, State fossil — Minnesota Office of the Revisor of Statutes (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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