How old are Keokuk geodes?
Most of the geodes are derived from the lower Warsaw Formation, a widespread rock unit of Mississippian age. Calcium carbonate and clay muds deposited in a shallow sea about 340 million years ago were subsequently lithified to form the shales, shaley dolomites, and limestones.
Why are there so many geodes in Keokuk Iowa?
The magic of Keokuk Geodes, for collectors, mostly comes from the secondary and rarer crystal formations found in the region. Keokuk geodes hail primarily from the Lower Warsaw Formation, which is a shale layer that’s preserved many fossils in Iowa.
What is the rarest type of Geode?
amethyst crystals
The rarest and most valuable geodes contain amethyst crystals and black calcite.
Where do I get Keokuk geodes?
Iowa’s renowned Keokuk geodes can be found in specific stream drainages and excavations in parts of southeastern Iowa (especially in Lee, Henry, and Van Buren counties), including the area near Geode State Park.
What is the most expensive geode?
The Most Expensive Geodes For example, some of the most expensive and valuable are amethyst geodes. Just take a look on some of the online geode marketplaces and you’ll see right away that amethyst geodes are worth quite a bit. Some ranging well into the thousands of dollars!
Do geodes keep growing?
As water flows through the geode, additional mineral layers are deposited in its hollow interior. Over thousands of years, these layers of minerals build crystals that eventually fill the cavity. How long this takes depends on the size of the geode — the largest crystals can take a million years to grow.
What is my geode worth?
Large amethyst geodes can go for thousands. Baseball sized geodes with non-spectacular quartz or calcite crystals can be purchased for $4-$12. Geodes with uncommon minerals that are sold on mineral auction sites range in price from $30-$500. Golf ball sized geodes, uncracked, are sold for about $2 at shows.”
Where Can You Dig geodes in Missouri?
The best places to find geodes in Missouri:
- Alexandria & Wayland – In creek and river banks.
- Fox City – North of an iron bride along the river.
- Kahoka – In outcrops along the Fox River.
- St. Francisville – In Weaver’s Branch creek.
- Fabius River – East of Durham.
- Arnold – On the west side of I-55.
Where can I mine crystals in Iowa?
The best places to find crystals and gemstones in Iowa are:
- Orient – Agate, Quartz crystals, Petrified wood.
- Bells Mill Park – Large black calcite crystals.
- Bellevue – Agate, Moonstone, Carnelian, etc.
- Burlington – Agate, Quartz crystals, Geodes.
- Mount Pleasant – Gem-quality colored Chert.
Where are the geodes found in the Keokuk formation?
Keokuk Geodes are collected from the Lower Warsaw Formation within about 100 miles of the city of Keokuk. There are over 300 known geode containing exposures. The main exposures are found in stream beds that are tributaries of the Mississippi River.
Where can geodes be found in the world?
To me, the process is very similar to how beautiful formations are built within caves, but on a much smaller scale. Geodes are found all over the world but one of the largest concentrations of them is found around Keokuk, Iowa in something called the lower Warsaw Formation, a widespread rock unit of Mississippian age.
Where are the geodes found in the Warsaw Formation?
Geodes can be dug out of exposures of the lower Warsaw Formation where they are concentrated in certain layers. Loose geodes can also be collected in stream channels where water has eroded the rock. Geodes from the Keokuk area contain a variety of minerals, but quartz is dominant in most.
Where is the Geode capital of the world?
The area around Keokuk, Iowa is sometimes referred to as “the geode capital of the world. Geodes have been collected from the Lower Warsaw Formation within about 100 miles of the city for over 150 years. Keokuk geodes contain a variety of minerals, but quartz is dominant in most.