
A conulite, also called a mud cup, is a type of dripstone that forms when water drips into a soft sediment, both eroding the sediment and depositing calcite. Because they form in soft sediments when those sediments are washed away, these formations are left standing like ice cream cones stuck in mud. These formations can be white and often have cave pearls inside them.
When dripstones (specifically stalagmites) form, they will sometimes create a conulet first, making a kind of 'root' for the stalagmite.
There are a few variations on cave conulites formed in very similar ways but different enough to have their own names.