A jar is a rigid, approximately cylindrical container with a wide mouth or opening. Jars are typically made of glass, ceramic, or plastic. They are used for foods, cosmetics, medications, and chemicals that are relatively thick or viscous: pourable liquids are more often packaged in a bottle. They are also used for items too large to be removed from a narrow neck bottle.The glass jar is often an essential for any kitchen cupboard. They can be used to preserve or store items as diverse as jam, pickled gherkin, other pickles, marmalade, sundried tomatoes, olives, jalapeño peppers, chutneys, pickled eggs, honey, and many others. They are also frequently re-used in order to put home-made preserves in. Jars are sterilised by putting them in boiling water or an oven for a number of minutes. If they are not required for further storage of items, they can be recycled.A closure applied to the mouth of a jar can be a screw cap, lug cap, cork stopper, or other suitable means.Glass jars are considered microwavable with care taken to prevent splashing of boiling contentsJars are often recycled according to the SPI recycling code for the material. Some regions have a legally mandated deposit which is refunded after returning the container to the retailer. Some recyclers have concerns about possible residue in the jar from the viscous contents.