SSEF laboratory offers analysis of precious stones and issue test reports for diamonds, coloured stones and pearls. It was recognized in 1978 by the International Confederation of Jewellers and Goldsmiths (CIBJO and also a member of the International Colo
Any array of electromagnetic visible light ordered according to its constituent wavelengths or colors, when the white light is dispersed by a prism or diffraction grating, ranging from about 750 to about 400 nm. The spectra can obtained by means of spectr
A small hand optical device for obtaining and visually observing spectrum, in which collimated light passes through a narrow slit onto either a prism or diffraction grating, its spectrum being viewed by a lens system or telescope. The angle between the c