A weighing jar, also known as a weighing bottle, is a specialized container used in laboratories for precisely weighing samples. These bottles are typically made of borosilicate glass or polypropylene and come in various sizes, ranging from 5ml to 360ml. Borosilicate glass offers excellent chemical and thermal resistance. They are designed with ground glass stoppers to ensure an airtight seal, which prevents moisture absorption and maintains sample integrity. Some may also have PTFE stoppers available. The design, either tall or low form, ensures stability on balance pans for accurate measurements.
Several manufacturers offer weighing bottles, including SAMTECH Instruments, Eisco Labs, Kimble (DWK Life Sciences), Borosil, Medilab and StonyLab. These bottles are essential in pharma, chemical, academic, and quality control laboratories. Features often include a smooth inner surface to prevent sample adherence, autoclavability for sterilization, and durability for rigorous use. Prices vary based on size and material, with individual bottles ranging from approximately $5 to $12, while sets can cost around $50. They can be found at lab supply retailers such as Avogadro's Lab Supply, Thomas Scientific, Fisher Scientific, and U.S. Plastic Corp. Weighing bottles are generally available, though specific sizes or materials may occasionally be on special order.
