Devices and methods for securely storing data are provided. A device for constructing an encryption key comprising a tamper-protection barrier that encloses one or more memory devices is provided. The memory stores data for constructing the encryption key. The memory may include a single memory device or a plurality of memory devices. The tamper-protection barrier also encloses a security processor configured to combine the data stored in the memory based in part on a function, such as a logical exclusive-or (XOR) function, to construct the encryption key. The stored data in the memory may include partial keys. These partial keys may be created based in part on applying the XOR function to an encryption key.