it is the normal beige cream but the very light vains are slight aqua green they only reflect when light hits it does seem hard but does create a good milky slurry i supose would be fine for maintanance and polishing i have kosher that is pure in colour just speckled yellow seems about same hardness but feels only slightly smoother when i run a razor across the khosher they both seem to do the same job. have you ever used just your yellow with light slurry and then plain water and achieved a nice egde jimmy.
Absolutely. As Howard frequently points out, barbers used the coticule for a hundred years and got keen shaving edges off of them.