The Leica gemstone microscope is a category of high-end stereomicroscope produced by Leica Microsystems and configured (usually as part of the M-series or A60 series, with appropriate gemmological accessories) for the examination of gemstones at the laboratory and high-end retail level. The German optical heritage, the parfocal zoom system, and the integration with Leica's full ecosystem of dark-field stages, fibre-optic illuminators and digital imaging modules combine to produce an instrument that is widely regarded in the gemmological community as a premium reference tool.

A typical gemmologically-configured Leica setup uses the M205 series (or earlier M-series) zoom body with magnification ranging from roughly 7.8x to 160x, mounted on a dark-field gem stand with a built-in transmitted-light base, fibre-optic illumination arms (LED, with adjustable colour temperature), a stone-holder accessory for hands-free positioning of loose stones, and an optional digital camera or microscope-camera coupling for laboratory documentation. The optical quality, particularly the colour fidelity and the depth of field at high zoom, is the principal reason laboratories specify Leica over less-expensive alternatives.

For the working bench the practical significance is professional standards. Major laboratories (GIA, Gubelin, GRS, AGL among others) use Leica or comparable Carl Zeiss instruments for examination work, and a high-end retail or estate-jewellery operation specifying a Leica is signalling that its bench examination is to laboratory standard. The capital cost is substantial relative to entry-level jewellers' microscopes; the differentiating performance shows itself in inclusion examination, fluorescence-stage work, and high-magnification photographic documentation.