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The Worlds Largest Geode (And How It Was Found!)

Is This The Worlds Largest Geode?

This is the second post of my “Interesting Things From Around The Internet” series. If you missed the first, you can check it out here.

Could you imagine digging a well on your property only to run into a large cavern around 40 feet below the surface? And then, once you climb into the pitch black cavern to explore the new discovery, you lift your lantern up and you see that the large cavernous space is completely lined with massive 8 to 18 inch long celestite crystals?

Well that’s exactly what happened to the workers in 1897 who were digging a well for Gustav Heineman and his Heineman Winery in Put-In-Bay, Ohio which is on a small island called Bass Island located in Lake Erie, about half way between Cleveland and Toledo.

What Mr. Heineman didn’t know, however, was that he and his workers had just discovered the worlds largest geode! (Want to learn more about geodes? Click here)

inside the worlds largest geode
Photo Credit:

The inside of the geode is about 35 feet in diameter at its widest point, is 12,000 to 16,000 years old and is made of almost pure celestite. Some to the largest crystals are as large as three feet long! Some of the Heineman Geode crystals are even on display in the Smithsonian Natural History Museum in Washington D.C. according to one visitor to the cave.

But little did Gustav Heineman know how fortunate he was in finding this incredible geode. Because in 1920, the United States began the prohibition of alcohol, and that meant the Heineman winery was out of business and in jeopardy of losing everything.

large crystals inside the worlds largest geode

Photo Credit:

While other wineries on Bass Island and around the country began to close, the Heineman winery decided to start giving tours of the crystal cave. This decision helped save the family winery from closing and saw it through until the end of prohibition in 1933.

In addition to tours, the Heineman’s were also able to earn an income from harvesting the crystals and selling them to a fireworks manufacturer. As it turns out, the soft celestite crystals, when ground into a fine powder, will burn a deep crimson red. As a result, the cave used to be much smaller than it is today. I can only imagine how many crystals must have been removed from the cave.

Interested In Visiting The Worlds Largest Geode?

Now I’ve never been to see this massive world renown geode for myself, but heck, it’s at a winery, so what’s not to like about that!

According to the Heineman Winery website, tours of the cave and the winery are offered for $8 for adults and $4 for children ages 6 to 11. Tours are offered seven days a week from early May until late September. Monday through Saturday, tours of the cave begin at 11 a.m. and continue throughout the day until 5 p.m. On Sunday, tours begin at 12 p.m. and continue until 5 p.m.

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