Felsic Rocks
Ultramafic igneous rock contains the least silica.
Peridotite, a type of ultramafic rock composed largely of the mineral olivine, has the least silica.
Peridotite, a type of ultramafic rock composed largely of the mineral olivine, has the least silica.Read more: Which_igneous_rock_out_of_granite_basalt_andesite_and_peridotite_has_the_lowest_silica_SiO2_content
The rock is likely rhyolite, which is a light-colored igneous rock with high silica content. Rhyolitic magma is viscous and tends to trap gas, leading to explosive eruptions with ash and pyroclastic flows. The high silica content of rhyolite contributes to its light color and explosive nature.
The higher the silica content in an igneous rock, the lighter the overall color. This is because silica-rich rocks tend to be lighter in color due to the presence of minerals like quartz, which is typically white or light-colored. On the other hand, rocks with lower silica content tend to be darker as they contain minerals like mafic minerals (such as olivine and pyroxene) which are dark in color.
Ultramafic igneous rock contains the least silica.
Peridotite, a type of ultramafic rock composed largely of the mineral olivine, has the least silica.
Peridotite, a type of ultramafic rock composed largely of the mineral olivine, has the least silica.Read more: Which_igneous_rock_out_of_granite_basalt_andesite_and_peridotite_has_the_lowest_silica_SiO2_content
An igneous rock's color is mainly determined by its silica content.
Granite is actually high in silica, which is why it is considered a felsic igneous rock. An example of an igneous rock low in silica is basalt, which is mafic in composition and contains less silica than granite.
Basalt.
The more silica contained in a rock, the lighter in color it will be.
The more silica contained in a rock, the lighter in color it will be.
The more silica contained in a rock, the lighter in color it will be.
The rock is likely rhyolite, which is a light-colored igneous rock with high silica content. Rhyolitic magma is viscous and tends to trap gas, leading to explosive eruptions with ash and pyroclastic flows. The high silica content of rhyolite contributes to its light color and explosive nature.
Basalt is an igneous rock with low silica content that flows easily due to its low viscosity when molten. It often forms from volcanic eruptions and is found in oceanic crust and volcanic islands. Basalt is dark in color and fine-grained, with a composition of around 45-52% silica.
I would expect a light gray igneous rock to be rich in silica. Light gray color in igneous rocks is often associated with high silica content, which is typical of felsic or granitic compositions.