Cauldrons are a basic item for any witch or wizard. These versatile items are used to brew potions, but can also be used to carry supplies, and, in a pinch, to clobber an attacker.
Many cauldrons seem to be at least partially magical. Self-stirring, collapsible, and other cauldrons are for sale in a shop on Diagon Alley, for example (PS5).
Young Bruno Schmidt of Germany hit an Erkling over the head with his father's collapsible cauldron and killed it (FB).
Fire-Crab shells, which resemble tortoise shells encrusted with jewels, are prized by unscrupulous wizards as magical cauldrons (FB)
Gaspard Shingleton invented Self-Stirring Cauldrons (FW), a fact which the first years had to remember for their History of Magic exam at the end of the year (PS16)
In Diagon Alley, Harry saw cauldrons made of Copper, Brass, Pewter, Silver, and solid Gold (which Hagrid would not let him buy) (PS5). The award for the Wizarding Schools Potions Championship is a gold cauldron (BoP). Different metals seem to lengthen or shorten brewing times for potions (Pm).
Cauldrons can carry a lot of books, which suggests that they might have enchantments on them to make them bigger on the inside than they are on the outside such as the Undetectable Extension Charm or wizard space (CS4)
Neville melted his sixth cauldron in Potions.
Percy spent a lot of time while working in the Department of International Magical Cooperation writing a report about the need to standardize cauldron thickness to prevent the market being flooded with defective thin-bottomed imported cauldrons (GF5).
Although they own their own cauldrons, when the students come into their Potions class, twenty cauldrons are already in place, waiting for them. Perhaps they use school cauldrons in class and their own to practice the techniques... (PS8)
A wizard named Humphrey Belcher believed "the time was ripe for a cheese cauldron." He was wrong (HBP10).
The word cauldron is first recorded in Middle English as caudroun (13th century). It was borrowed from Old Northern French or Anglo-Norman caudron (Norman-Picard caudron, French chaudron). It represents the phonetical evolution of Vulgar Latin *caldario for Classical Latin caldārium "hot bath", that derives from cal(i)dus "hot".
Cauldrons have largely fallen out of use in the developed world as cooking vessels. While still used for practical purposes, a more common association in Western culture is the cauldron's use in witchcraft—a cliché popularized by various works of fiction, such as Shakespeare's play Macbeth. In fiction, witches often prepare their potions in a cauldron. (Wikipedia)