Agate Central
In Moose Lake State Park, an interpretive center caters to rockhounds.
© Beth Gauper
Raw agates and stones on a Lake Superior beach.
To some people, nothing is a finer destination than the dusty gravel pits around Moose Lake in northern Minnesota.
A billion years ago, when fresh lava was cooling around what is today Lake Superior, dissolved minerals flowed into gas
bubbles that had formed on top layers.
Other minerals coated the first layers, some red from iron or white from calcium, and over time heat and pressure squeezed them into stone.
Then, the glaciers came, fracturing the surrounding rock and freeing the agates. Pushed along by ice, they were tumbled, polished and eventually dumped along with other glacial rubble.
Carlton County is on the rim of the basin that once held Glacial Lake Duluth, and its gravel pits have drawn rockhounds for
years.
Now, agate hunters also can visit the Moose Lake Agate and Geological Interpretive Center at Moose Lake State Park, just off Interstate 35 on the way to Duluth.
Naturally, it contains a magnificent collection of Lake Superior agates, the Minnesota state gemstone. Like snowflakes, no two are alike.
Some are classic red, with wavy circles of white; others are the gray shades of a rainy day or colored with golds, greens and purples. One bears the number 8 in concentric layers of orange and white; another bears the image of an owl.
Wall exhibits explain agate formation and other geological history. In the "Rock Around the Clock"' exhibit, clocks set between noon and midnight show how and when Minnesota formed.The clock already is at 10:30 p.m. by the time ore is deposited on the Iron Range and lava cools on the North Shore; by the time man appears, it's already 11:55 p.m.
Admission is free to anyone with a state-parks vehicle pass; otherwise, it's $7 per car.
For good hunting, bring gloves, a bag, tongs and a spray bottle full of water with which to spritz likely looking rocks; the best time to hunt is early or late on a sunny day, when the sun's rays slant across the rocks.
For more, see How to find an agate.
Agate Days in July is a particularly good time to visit Moose Lake. The Carlton County Gem & Mineral Club holds a free
rock show at the high school and sponsors the annual Agate Stampede, when tons of gravel are dumped on a downtown
street and rock hunters are invited to pick through the rock for 350 pounds of agates — and $300 in quarters.
For more, see Agate stampede.
Permits to hunt agates
Moose Lake, half an hour south of Duluth off I-35, is renowned for its gravel pits.
You can print out your own free agate-hunting permit from the Moose Lake Chamber of Commerce website, which includes a map to the gravel pits.
Any area that's been disturbed can yield agates, including ATV trails. Railroad tracks and roadsides also yield agates; many savvy hunters stop whenever they see road construction.
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