Question

Terra Sigillata in kind of -

• A. glaze
• B. engobe
• C. oxide
• D. clay

Hint:

Logic Tip: Terra Sigillata is just super-fine liquid clay painted on a pot. Liquid clay painted on a pot is called an engobe (or slip).

Answer 1

The Correct Option is B

Concept:
Terra Sigillata is an ancient ceramic surface treatment heavily used by the Greeks and Romans to create smooth, sealed, and subtly glossy surfaces on their pottery.

Step 1:
"Terra Sigillata" literally translates to "sealed earth."

Step 2:
It is made by taking highly plastic clay, mixing it with water and a deflocculant (like sodium silicate), and letting it settle. Only the finest, most microscopic, nano-sized clay particles remain suspended at the top. This ultra-refined liquid clay is what is used as Terra Sigillata.

Step 3:

• It is not a glaze because it contains no glass-formers (silica/fluxes) designed to melt into a liquid glass.
• It is not an oxide (which is a raw chemical colorant).
• While made of clay, as a surface application, it acts as a coating.
• An engobe is defined as a liquid clay slip applied to the surface of a ceramic body to alter its color or texture.

Step 4:
Because Terra Sigillata is an ultra-refined liquid clay applied to the surface of a pot, it falls under the technical classification of an engobe or slip. \[ \boxed{\text{(2) engobe}} \]