The first important property of faience is "its own" sound. When tapping with a wooden stick the faience object makes a dull sound. A porcelain product will always "answer" with a melodious ring.
The second property is the massiveness of the forms and the vagueness of the reliefs; moreover, the earthenware is always thick-walled. All reliefs on the surface have smooth lines without fine, clear details. The objects are impenetrable to the lumen, it is impossible to see the light through their walls.
The third property - the color of the earthenware is never white. You can always watch the cream shades and even small patches in the structure of the material at the break.