Deer or elk hair

Have a pile of this to sell, but don't know how to tell the difference. Any hints?

Here’s a decent description of the differences in ungulate hair

https://midcurrent.com/flies/fly-tying-hair-selection/

Regards,
Scott

Thanks for the link

This is also a great article on deer hair and it's various characteristics by the late Chris Helm:

Selecting deer hair | Global FlyFisher | Choosing the right hair will make your deer hair flies - Comparaduns, EHC's, Muddlers, bass bugs - much easier to tie.