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.
Metamorphic rock is formed underground through a process that changes a rock's molecular structure due to pressure, heat and chemical reactions. A metamorphic rock forms from a parent rock called a protolith. Depending on conditions, a protolith can transform into any metamorphic rock. Because protoliths are capable of undergoing vast changes, identifying them is sometimes difficult for geologists.