Why White Granite Has A Smaller Grain Size Than Rhyolite

Rhyolite is the felsic igneous rock with fine grained size.

Why white granite has a smaller grain size than rhyolite.

The difference is the size of grains. Occasionally it is light gray. Smaller than granite i think you can change the grain size of a metal by heating it up to its melting point and then allowing it to cool again. Granite is available in black grey orange pink white colors whereas rhyolite is available in grey white light black colors.

Rhyolite which cools at the surface cools much more quickly than granite which cools underground. The rapid cooling only allows small crystals to form. It frequently contains voids and glassy fragments evidence of having formed in a surface environment with. It is composed of the light colored silicates and is usually buff to pink in color.

Here is the actual problem that my homework says. Whereas granite is the equivalent in. Why does rhyolite have smaller crystals than granite. Rhyolite and granite have the same chemical composition and are formed from the same type of liquid rock.

Ok i have this science homework that wasn t assigned at all until last minute notice so its mostly about comparing the two types of minerals. It has a composition similar to granite but has a much smaller grain size. Rhyolite has smaller crystals than granite because rhyolite formed from lava and granite forms from magma. Rhyolite is an extrusive igneous rock a felsic silica rich volcanic rock that includes obsidian and pumice.

In texture it is classified as aphanitic. Since granite cools underground from magma largecrystals form because the magmahas a chance to cool slowly. Appearance of granite is veined or pebbled and that of rhyolite is banded. This doesn t allow a lot of time for crystals to grow in the rock.

Rhyolite which cools at the surface cools much more quickly than granite which cools underground. Rhyolite has a composition similar to granite but has a much smaller grain size. Natural glasses like obsidian rhyolite glass cool so quickly that mineral grains do not have time to grow. The rapid cooling only allows small crystals to form.

It is composed of the light colored silicates and is usually buff to pink in color. Why is the grain size of rhyolite less than 1mm while the grain size of granite is greater. The longer it takes to cool the larger the grain.