A compact adapted to package a cosmetic in paste or cream form that includes volatile agents, the cosmetic package being hermetically sealed to prolong its shelf-life. The compact is provided with a case on whose base is anchored a cylindrical shell for storing the cosmetic. Surrounding the shell is an elastomeric sealing collar having a circular array of elastomeric legs extending from its lower edge and resting on the base of the case. Formed on the inner surface of the lid is a circular pressure ring which when the lid is swung down to close the compact then engages and applies downward pressure to the upper edge of the sealing collar to hermetically seal the cosmetic stored in the shell. This action compresses the legs which then exert an upward pressure on the collar to tighten its engagement with the ring and thereby strengthen the seal.