A container is provided, comprising an upper portion with a circumferential sidewall defining therewithin a liquid-containing space, a base made of a non-opaque material and being disposed below the upper portion with an inner surface defining a downwardly-facing concavity, a plug disposed within the concavity and sealingly contacting at least a portion of the inner surface, and an article distinct from the plug and disposed within the concavity such that it is encased by the plug. The article is visible through at least the plug and/or the base.
