Gemstone detector
GE HealthCare's garnet-based CT scintillator — the first new commercial CT scintillator material in roughly 20 years at launch. The Gemstone detector shipped on Discovery CT750 HD and carried through Revolution HD / Apex generations. Faster primary light transfer and dramatically reduced afterglow vs conventional gadolinium-oxysulfide (GOS) scintillators — OEM positioning of ~100× the primary-speed performance of GOS. The fast afterglow is what makes Gemstone Spectral Imaging (GSI) fast-kVp switching practical.
Why it matters to buyers: The Gemstone detector is the load-bearing feature of GE's dual-energy CT strategy. It also supports high-definition reconstruction modes at finer spatial resolution than conventional CT detectors of its era.
Why it matters to engineers: Detector service on Gemstone-era GE CT uses Gemstone-specific part numbers. Scintillator afterglow and DQE testing are part of periodic QC on HD-mode-capable scanners.