100 years per inch
It's prehistoric. Can't remember what they said or if they could, but info was given on the time it takes for stalagmite growth which is extraordinarily slow, also prehistoric fossils present from a time when it was in the ocean. A shark took even!!!
The cave took more than 100,000 years roughly. It all starts with water combining with CO2 to create carbonic acid, this eats the limestone away. Take some soda and put it on a piece of limestone (soda pop has carbonic acid), and you will get the idea. Once a crack starts, that becomes a water way, the water supports the ceiling, until a new course opens up, as the water level drops the ceiling will collapse, making the cave bigger. This will happen until the cave gets a dome or cathedral ceiling (the most stable ceiling). Then the cave begins to "decorate" its self. That uses the same process that created the cave, except when the water carrying mineral it has eaten away, hits air it loses CO2 and the mineral is left behind. Hope that helps explain why I gave such a long time span.
To form a stalagmite 100 years
The guides are very knowledgeable. Ours was a geologist.
Millions of years
Elijah Beld. For every inch of growth 100yrs
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