Dugway Geodes
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Museum Specimens
6 to 8 million years ago, volcanic activity in Western Utah deposited an igneous rock called rhyolite. Trapped gases
formed pockets in the rhyolite, which eventually became lined with chalcedony and quartz from groundwater. Most
Dugway Geodes fluoresce a lime green color due to minute amounts of a secondary mineral that bonded with the
quartz when it was growing. The fluorescence comes from uranium salts trapped in the Chalcedony. The level of
uranium is so low though, that it is undetectable, and totally harmless.

32,000 to 14,000 years ago, Lake Bonneville covered most of Western Utah. The lakes wave motion activity eroded
the rhyolite and actually moved the geodes several miles away to their current location near the town of Dugway in
Juab County, Utah. They are called Dugway Geodes because that is the only place on earth these are found!

Located on the edge of the salt flats of the Dugway Proving Ground, these West Desert geode beds are one of Utah’s
most popular rock collecting sites. Their convenient location near the gem collecting area of Topaz Mountain make
them an excellent companion stop for a family trek to the Thomas Range. This property is controlled by the Bureau of
Land Management (BLM) public lands. Active mining claims exist on some portions of the "geode area" so seek
permission from the claim owners before collecting. For more information on BLM public lands under claim contact
the House Range/Warm Springs BLM field office at (435) 743-3100.

Until recently, the best known free collecting claim was maintained by Loy Crapo of Delta, Utah. Since Loy’s passing,
his family has taken over management of the site. To justify the excavation and insurance expenses of maintaining the
site, visitors must now sign a liability waiver and submit a $30 fee per group to collect. In return, the Crapo family is
constantly excavating new collecting pits in the clay to ensure visitors have constant access to fresh material.
Item # 13DG09190993
Polished Face Fluorescent Dugway
Geode Half
$79.00
Exceptional Large Cabinet Chalcedony Chamber Fluorescent Dugway Geode. The large swirling vug is
like a cavern that is lined with fine druzy crystals. This is a very interesting piece. The back of the rind has
a chalcedony section exposed that also fluoresces green as shown in last two photos. The Chalcedony
fluoresces a brilliant Green under Short Wave Ultra-Violet Light. This specimen cut face is polished.
Fluorescent photos taken with a Nikon coolpix L1 camera with the specimen under a Way Too Cool 254
nm SW 9-Watt Lamp in a black out photo box. Non-fluorescent photos taken with same camera in
outdoor natural light.   

Measures 4.8 x 3.3 x 2 inches (12.4 x 8.5 x 5 cm) and weighs 20.4 oz or 1.28 lbs (581g)
Item # 14DG09192022
Polished Face Fluorescent Dugway
Geode Half
$49.00
Exceptional Large Cabinet Chalcedony Two Chamber Fluorescent Dugway Geode. The large two vugs
are like a cavern that each half is lined with fine druzy crystals. This is a very interesting piece. The
Chalcedony fluoresces a brilliant Green under Short Wave Ultra-Violet Light. This specimen cut face is
polished. Fluorescent photos taken with a Nikon coolpix L1 camera with the specimen under a Way Too
Cool 254 nm SW 9-Watt Lamp in a black out photo box. Non-fluorescent photos taken with same
camera in outdoor natural light.   

Measures 3.4 x 3.1 x 1.2 inches (8.8 x 7.9 x 3 cm) and weighs 6.7 oz or 0.41 lbs (190g)
Item # 15DG09193953
Polished Face Fluorescent Dugway
Geode Half
$78.00
Exceptional Large Cabinet Chalcedony Two Chamber Fluorescent Dugway Geode. The large two vugs
are like a cavern that each half is lined with fine druzy crystals with small white calcite cubes in the larger
vug. This is a very interesting piece. The Chalcedony fluoresces a brilliant Green under Short Wave
Ultra-Violet Light. This specimen cut face is polished. Fluorescent photos taken with a Nikon coolpix L1
camera with the specimen under a Way Too Cool 254 nm SW 9-Watt Lamp in a black out photo box.
Non-fluorescent photos taken with same camera in outdoor natural light.   

Measures 4.6 x 3.1 x 1.7 inches (11.7 x 8 x 4.4 cm) and weighs 10.7 oz or 0.67 lbs (303g)
Item # 16DG09194062
Polished Face Fluorescent Dugway
Geode Half
$41.00
Exceptional Large Cabinet Chalcedony Three Chamber Fluorescent Dugway Geode. The three vugs
are like caverns that are a botryoidal formation lined with fine druzy crystals. This is a very interesting
piece. The Chalcedony fluoresces a brilliant Green under Short Wave Ultra-Violet Light. This specimen
cut face is polished. Fluorescent photos taken with a Nikon coolpix L1 camera with the specimen under
a Way Too Cool 254 nm SW 9-Watt Lamp in a black out photo box. Non-fluorescent photos taken with
same camera in outdoor natural light.   

Measures 4.1 x 4 x 1.7 inches (10.6 x 10.2 x 4.3 cm) and weighs 12.6 oz or 0.79 lbs (358g)
Item # 17DG09193063
Polished Face Fluorescent Dugway
Geode Half
$69.00
Exceptional Large Cabinet Chalcedony single Chamber Fluorescent Dugway Geode. The vug is like a
cavern that has a botryoidal formation with a small stalactite and a blade formation that are all lined with
fine druzy crystals. This is a very interesting piece. The Chalcedony fluoresces a brilliant Green under
Short Wave Ultra-Violet Light. This specimen cut face is polished. Fluorescent photos taken with a
Nikon coolpix L1 camera with the specimen under a Way Too Cool 254 nm SW 9-Watt Lamp in a black
out photo box. Non-fluorescent photos taken with same camera in outdoor natural light.   

Measures 3.8 x 3.7 x 2 inches (9.7 x 9.3 x 5.1 cm) and weighs 11.8 oz or 0.74 lbs (336g)
Item # 18DG09197113
Polished Face Fluorescent Dugway
Geode Half
$79.00
Exceptional Large Cabinet Chalcedony single Chamber
Fluorescent Dugway Geode. The swirl vug is like a
wonderous cavern that has several mountain ridges and
valleys lined with fine druzy crystals. This is a very
interesting piece that also looks like an image from outer
space with an eagle in the clouds on the right chalcedony
shelf. The Chalcedony fluoresces a brilliant Green under
Short Wave Ultra-Violet Light. This specimen cut face is
polished. Fluorescent photos taken with a Nikon coolpix
L1 camera with the specimen under a Way Too Cool 254
nm SW 9-Watt Lamp in a black out photo box.
Non-fluorescent photos taken with same camera in
outdoor natural light.   

Measures 3.6 x 2.7 x 1.25 inches (9.2 x 7 x 3.1 cm)
and weighs 8.8 oz or 0.55 lbs (252g)
On Reserve
for
Christy B