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Rock Hounding

Did you know?

A 5-Acre area along the Calapooia River is home to a lavender agate known as Holley Blue that is unique to Linn County.


Often called lavender chalcedony by jewelers, Holley blue is an agate. The jeweler's definition comes from its appearance. Chalcedony is a mineral made up mostly of crystals and quarts with tiny pores, and the stone is often semitransparent with a waxy luster and clouded with circles and spots. It's in the same family as carnelian, flint, jasper, and onyx.

While Linn County is a great place to hunt agates of all kinds, Holley Blue is currently the only one known to be a Linn County native. Additionally, it has been said that the 25-mile radius of Sweet Home is the widest variety and most quantity of any rock hunting location on the globe.

Sweet Home Rock & Mineral Society

The Sweet Home Rock and Mineral society is currently on hold due to Covid-19.

Contact Ed Anderson for details: 541-451-1577

Last Weekend in March

Sweet Home Annual
Rock-Gem & Mineral Show

Dealers, Raffle, Demonstrations,
Door Prizes and More

Admission: $.50
Children 12 and under:
FREE When Accompanies by an Adult

1641 Long St.
Sweet Home, OR 97386

Rock Background

Where to Hunt:

Rocks & Minerals: Petrified wood, blue and carnelian agates, geodes, and colorful jasper.
Tools Needed: Geology Pick
Counties: Linn
Road Access: OR 228 to Upper Calapooia Dr. and turn left. Petrified wood, blue and carnelian agates, geodes, and colorful jasper may be found in the gravel bed long the Calapooia River Bank. Public access to the river is limited, some collecting sites are available. Follow along the Calapooia River via Upper Calapooia Drive to find small pullouts where you can park and walk down to the river's bank. Follow for 18 miles, then take the right fork onto Forest Road NF 2820 which runs parallel to the Calapooia River, heading to the Willamette National Forest.   

Rocks & Minerals: Agate & Jasper
Tools Needed: Geology Pick
Counties: Linn, Benton, Polk, Marion, Clackamas
Road Access: Maintained

Rocks & Minerals: Petrified Wood, Agate, Jasper, Geode 
Tools Needed: Geology Pick
Countries: Linn, Benton, Polk, Marion, Clackamas
Road Access: Maintained 


Happy Sweet Home
Rock Hounding!

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