A computer system for assessing a histologically stained specimen, the system comprising: a) a microscope; b) a digital color camera attached to the microscope and configured to obtain a digital color image of the specimen; c) a library comprising a plurality of reference color signatures specific to biological features of histologically stained reference specimens; d) image processing circuitry configured to: i) define on the digital color image a region of interest "ROI" based on a biological feature of the specimen; ii) separate the digital color image into individual color channels; and iii) determine a color signature for the ROI, wherein the color signature comprises quantification of one or more color parameters over the ROI for one or more of the individual color channels; and iv) compare the determined color signature to one or more reference color signatures of the plurality of reference color signatures of the library to assess the histologically stained specimen, characterized in that the color signature comprises a first color coefficient calculated by determining the ratio of the mean intensity value for a first color channel to the mean intensity value for a second color channel; a second color coefficient calculated by determining the ratio of the mean intensity value for a third color channel to the mean intensity for the first or the second color channel; and a third color coefficient calculated by determining the ratio of the first color coefficient to the second color coefficient. a) a microscope; b) a digital color camera attached to the microscope and configured to obtain a digital color image of the specimen; c) a library comprising a plurality of reference color signatures specific to biological features of histologically stained reference specimens; d) image processing circuitry configured to: i) define on the digital color image a region of interest "ROI" based on a biological feature of the specimen; ii) separate the digital color image into individual color channels; and iii) determine a color signature for the ROI, wherein the color signature comprises quantification of one or more color parameters over the ROI for one or more of the individual color channels; and iv) compare the determined color signature to one or more reference color signatures of the plurality of reference color signatures of the library to assess the histologically stained specimen, characterized in that the color signature comprises a first color coefficient calculated by determining the ratio of the mean intensity value for a first color channel to the mean intensity value for a second color channel; a second color coefficient calculated by determining the ratio of the mean intensity value for a third color channel to the mean intensity for the first or the second color channel; and a third color coefficient calculated by determining the ratio of the first color coefficient to the second color coefficient. i) define on the digital color image a region of interest "ROI" based on a biological feature of the specimen; ii) separate the digital color image into individual color channels; and iii) determine a color signature for the ROI, wherein the color signature comprises quantification of one or more color parameters over the ROI for one or more of the individual color channels; and iv) compare the determined color signature to one or more reference color signatures of the plurality of reference color signatures of the library to assess the histologically stained specimen, <EOS>