Unknown, but one theory is appx 240m years. There is much that is still not understood about the mysterious geode.
The word "geode" comes from the Greek word "geoides," which means "earthlike" or "having the form of the Earth." Geodes are spherical rocks that contain crystals inside.
A geode with flint inside would be a type of geode that contains the mineral flint, a hard, sedimentary cryptocrystalline form of the mineral quartz. Geodes are typically round rock formations that contain hollow cavities lined with crystals or mineral deposits, and finding flint inside one would be an uncommon but interesting occurrence.
Geode is the scientific name. It is derived from Greek and means "earthlike."
Its simple, see a lot of people would have guessed a geode is a mineral or a gem. But its not. Geode is a sedimentary rock so instead of looking for the luster steak and hardness look facts on it like from its sedimentary form. A geode might have minerals in it, but that doesn't make it a mineral itself.
The largest geode ever discovered on the planet is The Almeria Geode, in Almeria, Spain. It measures 8 meters in length, 1.8 meters wide and 1.7 meters high (26' x 6' x 6'). See http://news.bbc.co.uk/2/hi/science/nature/787776.stm for more information.
it can take hundreds of years just to form half
a homemade geode could prob take about 7 days
the empress geode of urnguary
A geode. Geodes are spherical to oblong rock formations that contain hollow cavities lined with crystals such as quartz, amethyst, or calcite. They form as gas bubbles in volcanic rock or in sedimentary rock.
The word "geode" comes from the Greek word "geoides," which means "earthlike" or "having the form of the Earth." Geodes are spherical rocks that contain crystals inside.
A geode with flint inside would be a type of geode that contains the mineral flint, a hard, sedimentary cryptocrystalline form of the mineral quartz. Geodes are typically round rock formations that contain hollow cavities lined with crystals or mineral deposits, and finding flint inside one would be an uncommon but interesting occurrence.
The geode crystal for February is Amethyst
I'm taking this geode with me.
Geode is a rock or stone with crystals.
a geode
The found the geode while travelling through the caves. This is a sentence containing the word geode.
I have a geode which has been cut in half and polished