Use a CR-series Minolta chroma meter and record values in L a b tristimulus values system.  That could work and it will give you analyzable data.

Munsell Color Chart

Thre were comparisons suggesting Munsell's one for better discrimination power as in http://www.jstor.org/stable/25065433?seq=1#page_scan_tab_contents

If you are looking for common names try shades of brown a Wikipedia.( https://en.wikipedia.org/wiki/Category:Shades_of_brown)  I use these color names when describing plant and seed shades.

Use minolta chroma meter