What’s the difference between a mold and a cast?
Fossil molds and casts preserve a three-dimensional impression of remains buried in sediment. The mineralized impression of the organism left in the sediment is called a mold. The mineralized sediment that fills the mold recreates the shape of the remains. This is called a cast.
What is the difference between a mold and a cast quizlet?
What is the difference between a mold and a cast? A mold is a hollow space in a sediment in the shape of an organism or part of an organism. A cast is a copy of the shape that made the mold.
How does a mold and cast form?
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.
What are molds and casts?
Molds and casts are three-dimensional impressions in which the surface contours of an organism are preserved. Organisms buried in sediment slowly decompose, leaving a cavity that contains an exact imprint of the organisms’ shape and size.