Following the idea of Standard Tapered, in which conically tapered ground glass joints connect different parts, these jars are stackable, making the bottom of each one a “lid” for another one.
All lids are done in different materials, emphasizing a particular function related to things usually kept in jars. Marble and/or porcelain is used as a small mortar to ground fresh spices. Wood works as a small cutting board. Cork represents a traditional use of the material to cover jars and food-safe silicon provides a tight closure to prevent leaks and smells.