The cauldron symbolizes the goddess. When in use the cauldron symbolizes the womb because it holds something. When in use on an altar the cauldron represents the earth as it is a working tool used during ritual work. 
 
Uses of a cauldron:
Make herbal teas
Spell/ritual work
Place a candle inside to burn herbal blends during spell/ritual/wish work
Use as an oil burner by placing a candle beneath the cauldron
Altar decor
Burn charcoal with resin incense
Incense cones
Making brews
 
This is an classic style cauldron measuring approximately 15cm wide x 12.5cm high (excluding handle). Cast iron.