HAND-CRAFTED LEATHER GOODS
Descriptive terms used in connection with leather - continued
Case leather:- A non-specific term for leather with a glossy finish, excellent for stiff items such as travelling bags and suitcases. The basic material for case leather is run of the mill bovine hides, generally firm dressed splits.
Chamoising:- An ancient process which involves impregnating the skins with fish oils, then leaving them in a warm atmosphere for the oils to oxidise, i.e. react with the surrounding air. It is the current method for making soft "chamois" leather.
Centre cut suede:- This is a suede split that has had the edges trimmed to leave the bends and the shoulders behind, giving you the best and most useful part, the centre of the material.
Full grain - dark moss tumbled
Chrome tanned:- A leather tanned in chromium salts, primarily, standard chromium sulphate. It is tumbled in large drums, and the tanning process is correspondingly speeded up. Even the largest hide only taking a day to complete its tanning. This gives soft, mellow hides which react very favourably to many different dyeing processes, thus enabling an excellent colour variety. This method of tanning is currently the most widely used in America, thus its consumption is correspondingly enormous, though the method is normally limited to small skins, never usually larger than pigs or calves. The interior of chrome leather has a grey-blue-green tint, thus making it easily recognisable, unless it has been heavily dyed. Its feel is springy and flexible. It has water resisting qualities which makes it an unsatisfactory leather for cut-edge work where the edges are finished with water stain. Another point worth a mention is that the chromium salts used to tan the leather can corrode and dull your scissors and knives when you're cutting the leather. A very good reason for not making knife pouches or sheathes from it.
Comber Leather:- Used on combing machines in the textile industry, this is a soft, mellow and tough leather, which is tanned from steerhides, heavily stuffed with grease, and usually hand boarded or otherwise softened.
Combination tanned:- Speaks for itself really. These are leathers tanned with more than one tanning agent, such as vegetable and chrome together, resulting in the leather having not only body, but softness.
Cordovan:- Leather made from the tight, and firm, shell portion of a horse's rump, or crup. (That part of the horse's rump behind the saddle. That's why the strap from the back of the saddle that passes under the horse's tail to prevent the saddle from slipping forwards is known as the crupper). In area it would be about 15-20 sq ft. It has very fine pores and a characteristic finish. It is also exceedingly durable.
Horsehide is not as readily available as cowhide — mainly, I suppose, because we don't eat too many horses. The French and the Belgians, however, do manage to chew up quite a few, so the skins are shipped over from Continental Europe to the US for tanning. Why aren't the skins tanned in Europe? I've never quite puzzled that one out. Most continental tanners I've quizzed on the subject have acted surprised and said there's never been a demand for them!
A horsehide is divided into segments roughly along the lines of a cowhide.
However, chrome tanned horsehide is extremely hard-wearing. Remember the old
war-movies and the long leather coats the Nazi SS officers used to swan about
in? Well, most of the real ones were made of chrome-tanned horsehide, which is
probably why you'll find they're still as good as new — if ever you manage to
lay your hands on one! Because of this, the shoulders and bends are chrome
tanned for use in the garment industry. They are highly sought after and, being
in short supply, can command a prohibitive premium price! So what does that
leave for vegetable tanning? Sadly, just the strips that are part of the rear,
or the croup; segments that are, incidentally, not the most desirable parts of
the horse's skin.
Tanning Cordovan leather, using mimosa, in
Tanning Cordovan leather, using mimosa, in Southern Japan
Now vegetable tanned horsehide is extremely firm-grained, dense and oily, which doesn't help when it comes to the process of wet-blocking. It needs to be immersed for ten times longer than cowhide to allow the water to penetrate fully and, once blocked, is not as rigid nor does it retain its shape as well as cowhide when dry. Some manufacturers have attempted to solve this problem by having the horsehide strips hard-rolled at the tannery, a process which involves wetting the leather, then passing it through stainless steel rollers under a pressure of some thirty-odd tons. This compacts the leather and renders it rigid — so rigid, in fact, that it acquires the nature and consistency of plywood. In this state, it is an absolute swine to work with! It is hard to cut, harder to sew, and makes anything but the most rudimentary process of wet-blocking virtually impossible.
What can we say in favour of horsehide? Price-wise it's more or less on a par with cowhide, though many manufacturers, for reasons best known to themselves, insist on charging a hefty additional premium. Don't pay it! From the supply point of view it may not be as plentiful as cowhide, but there's still enough of it to go around. Is it more durable than cowhide? My experience shows that it isn't. So what can we say about horsehide that we can't say about cowhide? Well, nothing really. On the other hand, we can say that cowhide holds its shape a lot better than horsehide. (See also Horsehide Here)
Corrected grain:- The grain side of the hide is abraded to remove, or at least minimise, perceived faults. It then has to be pigmented to cover the effects of the sanding process. The leather then has a grain printed on it resembling its natural grain. A topcoat of sealer is then sprayed upon the surface. Corrected grain leather is invariably known as top-grain leather.