You may notice that some of the FG bags (like the one in the photo) are made from Nubuck. This is not (as my young son used to think!) the skin of a rare and beautiful deer-like animal! Nubuck is simply top-grain* cattle leather that has been sanded or buffed on the outside, to give a slight nap (texture) of short fibres, producing a velvet-like surface. It is resistant to wear, and may be white or coloured. Nubuck is similar to suede but differs in that is created from the outer side of a hide, rather than the inner, as in the case of suede. Because of this, it is stronger, thicker and has a finer grain than suede. It is generally more expensive than suede and is very soft to the touch. Water drops will darken the leather temporarily but it will return to its original colour upon drying.
The word nubuck probably comes from new + buck (skin).
*top-grain leather is the second-best quality leather after full-grain.