Criteria for the best quality shell cordovan?

Whiskey shell is undoubtedly beautiful and its surface is really transparent due to its time-consuming vegitable tanning process and anilin dye finish.   If you take a closer look, you may notice some spots or dark dots on the surface of the shell.  This is apparent in case of lighter color shell such as Whiskey or Ravello.

I have been wondering if these are horse hair pores or some parts of the blood vessels.  Sometimes they are obvious and sometimes not noticeable.  What are they?  I asked Nick at Horween but he also didn’t know exactly.

“Some shells show those spots but I’m not sure as to if it is some structure within the hide or if it is the base of some of the hair.  Either way, the spots tend to absorb dye a little differently.   For whatever the reason, many of the shells that have these spots tend to be the smoothest and nicest.”

It’s quite interesting, huh?  When checking the quality of the shell, he softly folded the shell like this and rubbed with fingers to confirm how smooth the surface is...

By the way, this is the piece of scrapped Whiskey shell Nick cut out a good quality portion as a souvenir.  Can't believe this was about to be scrapped...  It looks enough beautiful!