This is a very early piece & doesn't have the hidden mouse or any hallmarks. Originally there was no interior egg, & “ZOE” was inscribed under the tail. Later pieces, an egg was added, “ZOE” was replaced with the HBC logo. Crown Stamp with Treble clef stamped on BASE indicates this piece was made sometime from July 1995 to autumn 1996 after which the stamp was applied to the bottom of the lid. No egg inside but also do not see Zoe under the tail feathers.