A system and process for classifying a piece of material of unknown composition at high speeds, where the system connected to a power supply. The piece is irradiated with first x-rays from an x-ray source, causing the piece to fluoresce x-rays. The fluoresced x-rays are detected with an x-ray detector, and the piece of material is classified from the detected fluoresced x-rays. Detecting and classifying may be cumulatively performed in less than one second. An x-ray fluorescence spectrum of the piece of material may be determined from the detected fluoresced x-rays, and the detection of the fluoresced x-rays may be conditioned such that accurate determination of the x-ray fluorescence spectrum is not significantly compromised, slowed or complicated by extraneous x-rays. The piece of material may be classified by recognizing the spectral pattern of the determined x-ray fluorescence spectrum. The piece of material may be flattened prior to irradiation and detection. The x-ray source may irradiate the first x-rays at a high intensity, and the x-ray source may be an x-ray tube.