Other attempts at color measurement of diamond were made in 1967 by SCHLOSSMACHER and PERIZONIUS in Idar-Oberstein with the Remission Spectrophotometer, made by the firm of Carl Zeiss, of Oberkochen.
Like the Electronic Colorimeter, the Remission
Spectrophotometer measures the light transmitted by a gemstone. Not only
blue and yellow wave-lengths
but the whole visible spectrum can be measured by means of a
monochromator. For each wave length values are co-ordinated which, when
plotted graphically, yield graphs, which can be evaluated by
calculation. By means of this process the color of all gemstones and
diamonds can be measured unequivocally and objectively. Such an
instrument is very costly and Its use time-consuming; it should be
reserved for research purposes since it is not suitable for practical
diamond grading.
| color-Measuring Instruments | Diamond Photometer |