A rock has been formed by the accumulation of bits of rocks that were originally formed by the release of heat by magma. How should this rock be classified?

igneous rocks

sedimentary rocks

metamorphic rocks

organic rocks

Every rock has characteristics that reflect its process of formation; these are used to determine whether the rock is igneous, sedimentary or metamorphic. For example, a rock with rounded grains cemented together is sedimentary, while one with a strong banding and orientation of minerals is metamorphic. Identification of rock types within the three divisions depends on the nature of the mineral grains, including their composition and size and relationship to surrounding grains; the way the rock occurs; how uniform it is; its hardness; how it reacts with acid; its colour; and the way in which it breaks. Before trying to identify a rock, break a piece off with a rock hammer. This will expose a clean, fresh surface