Tamper-proof and reusable high security seal

A high security reusable seal comprising first and second portions movable with respect to each other to define an open and closed position of the seal;

• a display opening in one of the first and second portions of the seal;
• at least first and second authentication members located in the seal and displayed through the display opening, the at least first and second authentication member including randomly generated three-dimensional identifying features,
• at least one moveable member within the seal allowing relative movement between the at least first and second authentication members when the seal is in the open position;
• wherein, when the seal is moved to the closed position, the closing causes pressure to be applied to at least one of said authentication member, preventing relative movement between the at least first and second authentication members and creating a first authenticating characteristic,
• when the seal is moved from the closed to the open position, the opening causes said pressure to be released, allowing free relative movement between the at least first and second authentication members and thereby canceling the first authentication characteristic, and when the seal is closed again, the closing again causes pressure to be applied to at least one said authentication member to prevent relative movement between the at least first and second authentication members, creating a second authentication characteristic which is different from the first authentication characteristic.