A method and apparatus for detecting an isotope. Embodiments can detect radioactive isotopes. Embodiments can utilize a detector that incorporates at least two sub-detectors. Each sub-detector can receive energy from an isotope and create a signal corresponding to the received energy. Each sub-detector can incorporate a detector element, such as a detector element incorporating one or more diodes, a detector element incorporating a crystal, a detector element incorporating a solid-state device, or a detector element incorporating a scintillator. The sub-detectors can be configured such that for each isotope to be detected at least two of the sub-detectors produce different output signals, or readings. In an embodiment, each sub-detector is configured such that when there are at least two sub-detectors exposed to the isotope each of the corresponding readings from the sub-detectors is different from each of the other readings.