Protected vegetable tanned calf. Made in Spain. Protected vegetable tanned calf (natural color) is a thicker and more rigid type of leather. Protected vegetable tanned calf is a full grain semi-aniline leather that was tanned with vegetable extracts. Aniline leather is the most natural looking leather but is coated with a light and transparent protection against moisture and fluids. It gives your item a unique aspect and touch: the light can play its part on the aging process while it offers a useful protection for everyday life.