â¢ SULTAN (noun). The noun SULTAN has 1 sense: 1. the ruler of a Muslim country (especially of the former Ottoman Empire). Familiarity information: SULTAN used as a noun is very rare. SULTAN (noun). The noun SULTAN has 1 sense: 1. the ruler of a Muslim country (especially of the former Ottoman Empire). Familiarity information: SULTAN used as a noun is very rare.
Fossils also form from molds and casts. If an organism completely dissolves in sedimentary rock, it can leave an impression of its exterior in the rock, called an external mold. If that mold gets filled with other minerals, it becomes a cast. An internal mold forms when sediments or minerals fill the internal cavity, such as a shell or skull, of an organism, and the remains dissolve. Organic remnants. In recent years, researchers have discovered that some fossils aren't just made of minerals.
Schist is a coarse grained metamorphic rock. If you look at a piece of this metamorphic rock you will be able to see crystals of the minerals that make up the rock. It comes from shale or at least at one time it was shale. So geologists say that shale is the parent rock. It is made up of clay minerals. Shale can metamorphose into slate, phyllite, schist or gneiss depending on the degree of heat and pressure. Schist has a greater degree of metamorphism than phyllite but less than gneiss. It is classed as a medium-grade metamorphic rock and is associated with regional metamorphism do to mountain building.