Lake Superior agates

Facts checked against official sources on November 11, 2026

Photo: Lech Darski, CC BY-SA 4.0, via Wikimedia Commons

At a glance

State gemstone: Since 1969 (Minnesota Statutes 1.147)
Age: Formed in lava flows about 1.1 billion years old
Colors: Red, orange and yellow, from iron
State parks: Rock collecting not allowed
Where the DNR points you: Public Lake Superior beaches, river banks, gravel pits with permission
Rarest find: About 1 in 10,000 agates is an "all-timer"

In this guide

What a Lake Superior agate is
Types of Lake Superior agates
How to spot one on the beach
Where you can and can't collect
Where the DNR says to look
Before you go agate hunting

Short answer: Lake Superior agates are banded quartz stones, colored red, orange and yellow by iron, that formed in North Shore lava flows about a billion years ago. The Minnesota Legislature made the Lake Superior agate the official state gemstone in 1969. The DNR says the public beaches along Lake Superior are a popular place to hunt for them. Collecting is not allowed in state parks, state recreation areas or scientific and natural areas, so the agates at places like Gooseberry Falls are look-only.

This guide is for anyone heading up the North Shore who wants to look for agates and stay legal. It covers where the stones come from, the clues collectors use to spot an agate among beach gravel, the types you might find, and exactly what the DNR rules say about collecting. Everything here comes from the Minnesota DNR, the Minnesota Secretary of State and the state's own statutes and rules.

What a Lake Superior agate is

The DNR's Lake Superior agate article tells the story in four steps:

Lava. More than a billion years ago, the continent began to split apart and "poured out massive, iron-rich lava flows." Those flows are exposed today along the north and south shores of Lake Superior. Gooseberry Falls State Park's DNR page dates them to about 1.1 billion years ago and says these basalt flows "are also the birthplaces of Lake Superior agates."
Bubbles. Water vapor and carbon dioxide were trapped in the cooling lava as "gas pockets or vesicles," most of them about the size of a pea.
Bands. Groundwater carrying iron, quartz and other minerals passed through those pockets and crystallized into "concentric bands of fine-grained quartz called chalcedony."
Ice. The Superior lobe glacier moved into Minnesota 10,000 to 15,000 years ago, freed agates from the lava, and spread them across northeastern and central Minnesota and far northwestern Wisconsin. The DNR calls the glacier "an enormous rock tumbler."

The color comes from iron. The DNR says the stone's "predominant red color comes from iron," and the amount of iron and oxidation sets the color of each band. Agates range from pea-sized to more than 20 pounds, though "such giant agates are extremely rare."

Why it's the state gemstone

According to the DNR, the 1969 designation realized "the dream of Mrs. Jean Dahlberg," a long-time rock hound who testified before the legislative committee considering the bill. The Minnesota Secretary of State lists it among the state symbols, and Minnesota Statutes section 1.147 declares it "the official gemstone of the state of Minnesota." The DNR's reasoning: it formed in Minnesota lava, its color comes from iron (the state's major industrial mineral), and its wide spread records the glaciers.

Types of Lake Superior agates

Type	What it looks like, per the DNR	How common
Fortification	Bands that connect around the stone "like the walls of a fort"	"The most common type"
Water-level (onyx-fortification)	Perfectly straight, parallel bands across all or part of the stone	A "common subtype" of fortification
Eye	Perfectly round bands or "eyes" dotting the surface	"One of the rarest" and among the most popular
Moss	"Tree-branch-shaped bits of minerals trapped in them"	Not stated
Waterwashed	An almost perfectly smooth natural surface	"Rare"
"All-timer"	2 pounds or more, with perfect shape, color and banding	About 1 in 10,000 agates

The DNR's agate snapshot adds that "large, exceptionally beautiful agates may be worth hundreds of dollars."

A Lake Superior agate from Duluth, Minnesota, with red and white fortification bands and small round eyes — Photo: Lech Darski, CC BY-SA 3.0, via Wikimedia Commons

How to spot one on the beach

The DNR says the banding is usually "not well exposed," so collectors look for other clues:

Peeled texture: band planes where the agate has broken, so it looks partly "peeled off like a banana skin."
Iron-oxide staining: found on nearly all agates, most often in "shades of rust-red and yellow."
Translucence: chalcedony lets light through and gives a glow. The DNR says "sunny days are best for observing translucence."
Glossy, waxy look, especially on a chipped or broken surface.
Pitted texture: small pits left on the outside by the mineral layer that lined the original gas pocket.

The quickest way to learn the look is to see real ones. The DNR's recreational geology page points to the Agate and Geological Center at Moose Lake State Park, which "showcases the Lake Superior Agate." The DNR also notes that the city of Moose Lake calls itself the "agate capital of the world" and holds Agate Days each July.

Where you can and can't collect

Place	Can you collect?	What the official source says
Minnesota state parks (including all North Shore parks)	No	"Rock collecting is not allowed in any state parks or state recreation areas" (DNR)
State scientific and natural areas (such as Iona's Beach)	No	"Rock collecting is not allowed in the state parks, state recreation areas, and state scientific and natural areas" (DNR)
Public beaches along Lake Superior	The DNR calls them "a popular place for hunting for agates"	Check posted rules for the specific beach and who manages it
Gravel pits	Only with the owner's permission	"You must obtain the permission of the private landowner to hunt in a gravel pit"
Private land	Only with permission	"Obtain permission from the landowner before collecting minerals on private land"

The legal basis is Minnesota Rules 6100.0900. It says no person in a state park shall "remove any state property," and the list it gives includes "geological formations." The rule names one carve-out, Hill Annex Mine State Park, but that park no longer exists: the DNR says it "was abolished as a state park by the Minnesota State Legislature in 2024" and is "permanently closed" (DNR). So no current state park allows general rock collecting. Collecting for scientific or educational purposes needs the commissioner's written permission, and so does collecting for resale or commercial use in any state park.

The DNR's parks page puts it plainly: rocks are not collected in parks "since the parks preserve the natural resources for everyone to enjoy. However, rocks may often be collected near a park."

What that means at Gooseberry Falls

Gooseberry Falls State Park has a shoreline picnic area called Agate Beach, and its DNR page names the park's lava flows as agate birthplaces. You can look and take photos, but leave every stone where it is. The same rule applies at the gravel beach where the Baptism River meets Lake Superior in Tettegouche, at Pebble Beach in Split Rock Lighthouse, and in every other North Shore state park. State parks require a vehicle permit, $7 a day or $35 a year. For the rest of the park, see the Gooseberry Falls guide.

Where the DNR says to look

The DNR names these as good agate-hunting settings:

Public beaches along Lake Superior.
"The banks or at the mouths of rivers." Its agate article names "waters that empty into Lake Superior along the North Shore" and the Mississippi River as popular hunting grounds.
Gravel pits, with the owner's permission. The DNR warns that some owners refuse because of injury concerns.
"Virtually any place with exposed gravel and rocks." Because the glacier spread them, the DNR says agates "can be found throughout much of Minnesota," not just on the shore.

Before you go agate hunting

Know whose land you are on. If it's a state park, recreation area or SNA, leave every rock where it is.
Get permission before searching a gravel pit or private shoreline.
Hunt on a sunny day, when translucence is easiest to see.
Learn the clues first: staining, a waxy look, translucence, pitting and a peeled texture.
Stay off wet, wave-washed rock. Lake Superior is cold all year. See our Lake Superior water temperature guide.