carbon: a chemical element that exists in its pure form as diamond or graphite, and is an important part of other substances such as coal and oil, as well as being contained in all plants and animals

fossil: the shape of a bone, a shell, or a plant or animal that has been preserved in rock for a very long period

impression: a mark made on the surface of something by pressing an object into it

amber: a hard, transparent, yellowish-brown substance that was formed in ancient times from resin (= a substance produced by trees) and is used in jewellery

crab: a sea creature with five pairs of legs and a round, flat body covered by a shell, or its flesh eaten as food

preserved: to keep something as it is, especially in order to prevent it from decaying or being damaged or destroyed

sediment: a soft substance that is like a wet powder and consists of very small pieces of a solid material that have fallen to the bottom of a liquid

tar: a black substance, sticky when hot, used especially for making roads

mineral: a valuable or useful chemical substance that is formed naturally in the ground

cast: an object made by pouring hot liquid into a container and leaving it to become solid

dinosaur: a type of reptile that became extinct about 65,000,000 years ago. There were many different types of dinosaur, some of which were extremely large.

trilobite: a simple, flat sea creature that lived in the earliest period of life on earth, with a hard outer layer and a body in three parts

fish: an animal that lives in water, is covered with scales, and breathes by taking water in through its mouth, or the flesh of these animals eaten as food