For our black leather, we currently work with MPG Industria Coneria Apollo and Conceria Walpier's Buttero. Both are 100% Veg Tanned Italian leather.
Each of them have a very slight matte glaze/sheen to them that gives them an incredibly clean look, while also being quite durable. Outside of being dark already - they will hold up better to scratching and will patina less when compared to un unglazed harness leather. With this, they do run a bit stiffer at first and require a good break in period like all of our leather offerings. Slight differences in leather thickness affect this break in period as well.