what is aquarium gravel made of?

Question

Which rock type in particular....Igneous? Sedimentary? or Metamorphic?

Answer 1

I believe gravel is made of sedimentary but I am not sure. I know I learned this in 6th grade but It's been a while. Here is some info I found for you question...

"Large gravel deposits are a common geological feature, being formed as a result of the weathering and erosion of rocks. The action of rivers and waves tends to pile up gravel in large accumulations. This can sometimes result in gravel becoming compacted and concreted into the sedimentary rock called conglomerate"

http://en.wikipedia.org/wiki/Gravel - source

Answer 2

It really depends on your gravel. Most natural and "painted" gravels are quartz (igneous) pebbles that have been tumbled. Some people use pea gravel from construction/landscaping sources for a more natural stone "look" and in addition to the quartz, there's tumbled granite (also igneous) and sandstone (sedimentary).

If you're talking a marine aquarium, the substrate is typically shell and coral rubble (none, it's produced by living organisms) or crushed aragonite (sedimentary).

"Gravel" in geologic terms refers to a size of any rock deposit between 2 and 64 mm. Here "gravel" is meant as the stuff you put on the bottom of the tank, and not all rock is suitable.

Answer 3

igneous or sedimentary but im not sure,

Answer 4

igneous

Answer 5

rocks