sedimentary rocks usually (limestone is the most common). they are very easily eroded away leaving a cavern or series of caves tunneling for miles interconnecting. This is very common in Missouri whom has thousands of caves due to its vast supply of limestone
A cave is is a natural cavity in rock that forms as a result of the dissolution of minerals. A cavern can also be a large cave that may contain several smaller chambers.
lascaux cave
Vug or pocket.
This is called a mold, a mold is when a fossil has a cavity in a rock, it turns into a fossil when it becomes a cast, so technically yes it is a fossil
A cast
yes
There are man made imitations but real granite is a natural rock.
They look like a regular clump of rock. They are called rough gemstones.
Rock caverns are not built they are eroded out of solid rock by natural processes.
Vug
Vug
An underground cavern is a large cave or chamber typically found beneath the Earth's surface. These formations are often created through geological processes such as erosion, dissolution of rock, or volcanic activity. Underground caverns can contain unique ecosystems and geological features.
its called a Geode.
It is called a mold.
It is called a mold.
This is called a mold, a mold is when a fossil has a cavity in a rock, it turns into a fossil when it becomes a cast, so technically yes it is a fossil
it is limestone
a cave is like an arch formed by the erosion of the sea. +++ It may be, but a cave properly is any natural, subterranean cavity of humanly-enterable size, and in scale anything from a small sea-cave (as above) to vast systems of passages and chambers like Mammoth Caves.
A cavity in the ground where organisms can be buried is called a hole. If sediment fills this hole the organism may become fossilized.
Erosion