Archaeologists name the different parts of ceramics after the different parts of the body. When sorting through finds, they first separate them according to what part of the vessel they came from. Pieces that are recognizable as part of a vessel are known as diagnostic fragments.
Archaeologists can use small fragments to figure out the shape of pottery by drawing the profile of the fragment, measuring the diameter using a ring diagram, and comparing the fragment to known shapes.
The material of pottery is called fabric. The fabric is made up of the clay and a tempering agent, which is mixed into the clay. The temper helps to strengthen the pottery, ensuring that the vessels do not explode during the firing process. Some examples of temper include sand, sea shells and crushed up grit from previously fired pots (grog).
Pinching and Throwing:
There are three principle means of making ceramic objects. The potter can shape the vessel with his hands, throw it on a wheel or press it into a mold. This last method is the most efficient in terms of mass-production.
After molding the clay, the potter dries and fires a pot. The process known as firing involves applying high heat to the object, making it harder and more durable. Clay changes colour while firing as the molecules are oxidized. In this amphora foot, you can see the grey colour of the raw clay indicating that the piece was not fired all the way through. Meanwhile, the black pottery fragment represents a piece that was over-fired and has become brittle.
Pottery can be decorated in many ways. Patterns can me carved directly into the clay prior to firing or the pot may be painted with black, brown or red slips (thin clay/mineral based washes). These patterns and colours can sometimes help archaeologists to identify the origin of the vessel.