The glacially deposited sands around Lake Winnibigoshish, Minnesota, contain abundant sediments from the igneous and metamorphic minerals of the Lake Superior basin. A sample includes pink garnets, green epidote, iron-rich red agates, black magnetite, and hematite.
Otta Phylte: Bluish-black, sometimes with scattered and varied warm hues and shades of brown. The naturally riven surface has a smooth mica sheen, but with scattered crystals of very hard metamorphic minerals proud of the surface giving this stone a unique character with extra grip.
Regional metamorphism Staurolite Mica Schist, Broken Hill District, New South Wales, Australia Step 4 - large, course crystals form With further metamorphism, the texture of the rock becomes much coarser and develops mineral banding. The large platy crystals of mica and large crystals of staurolite that form are stable at higher pressures and temperatures.
Regional metamorphism Andalusite Schist, Inkerman lead, south of Dunolly, Victoria, Australia Step 3 - schist forms As the temperature and pressure increase further, the mineral crystals become large enough to be visible to the naked eye. The slate becomes schist, which is still made up of mainly platy minerals like mica and chlorite but has other minerals forming larger crystals.
The fragment of the metamorphic rock eclogite in which the garnet that encased the ferric-iron-rich majorite sample was found in Northern China.-'Nesting doll' minerals offer clues to Earth's mantle dynamics | Geology IN
Rocks and Minerals Non-Fiction Passages and Assessments Bundle! Rocks & Minerals and literacy integration! This bundle is a great addition to any rocks and minerals unit. It includes a variety of non-fiction reading passage and multiple assessments on igneous, sedimentary, metamorphic rocks, the rock cycle, and so much more. Students will learn about rocks and minerals while reading comprehension passages and practicing writing skills.