Abstract: Tissue cassette apparatus includes a removable, hinged cover separate from the cassette base wherein the cover is easily attachable and detachable from the base without being frangible. The removable cover includes a hinge member portion mateable with a cooperable hinge member portion on the cassette base structurally formed so that the hinge member portions cannot be separated when the cover member is closed on the base, but easily can be separated when the cover member is in a predetermined, opened position. The cover member is rotatable about the hinge member to an open position permitting placement of a specimen within the cassette base and to a closed position containing a specimen within the cassette base such that the cover member can be removed from the cassette base by elastic flexing of the hinge member without substantial damage to the hinge member.