The minerals that form when magma crystallizes slowly deep underground areGroup of answer choicesvisible without a microscopeglassyvisible with a microscope only

The first minerals to crystallize from a magma are those with the lowest melting point.Group of answer choicesTrueFalseNext

If a magma that is rich in Silicon and Aluminum cools over thousands of years underground, it forms Granite. If it cools quickly when it erupts from a volcano, it forms Rhyolite.If a magma that is rich in Iron and Magnesium cools over thousands of years underground, it forms Gabbro (which is sold as "black granite" at home improvement stores). If it erupts from a volcano, it also forms a black rock, but because it cools quickly, the crystals can only be seen under the microscope/ This rock is  _________Although _________ not common on continents, this rock is the most common rock on Earth's surface, because it forms the ocean floor. It is also the rock that makes up the Hawaiian islands, famous for their beautiful volcanoes and river-like lava flows.Group of answer choicesobsidiangranitebasaltpumice

Extrusive rocksGroup of answer choicesare generally made up of large mineralsare made up of precipitatesare also called volcanicform deep under volcanoes

Sedimentary rocks hold clues toGroup of answer choiceshow minerals crystallize from magmapressure and temperature in Earth’s deep interiorprocesses that cause volcanoes to eruptenvironments that existed on Earth’s surface in the past

Mineral growth in magmas at the surface with temperatures around 800 to 1,300°C occurs in the following wayMultiple ChoiceIron and magnesium will link up with aluminum and the silicon-oxygen tetrahedron as magma temperature decreases to sequentially form four distinct and discontinuous families of minerals—olivine, pyroxene, amphibole, and biotite mica.Calcium will combine with aluminum and the silicon-oxygen tetrahedron to begin forming the plagioclase feldspar family, a continuous and gradational series of minerals.Both of these are correct.None of these choices are correct.