The earth.
Are there rocks inside rocks? I keep asking everyone but they say they don´t know. Please help me! =(
"Rock" is not a typical definition (definitions usually include both a genus and a specific difference).
So it's hard to say yes or no as an answer.
Here's a good site about the concept of "rock."
"....there are no hard and fast boundaries between allied rocks. By increase or decrease in the proportions of their constituent minerals they pass by every gradation into one another, the distinctive structures also of one kind of rock may often be traced gradually merging into those of another. Hence the definitions adopted in establishing rock nomenclature merely correspond to more or less arbitrary selected points in a continuously graduated series."