HAND-CRAFTED LEATHER GOODS
Some of the many kinds of leather - continued
Glove leather:- A term used to describe soft leather used for gloves, which is normally lambskin. The term is also used by some to define soft leather.
Glutaraldehyde leather:- Leather tanned with glutaraldehyde (C5H8O2) a water soluble oil, usually in combination with other agents, to make the leather more resistant to deterioration under moist conditions. Glutaraldehyde has been used for some decades for the modification and stabilisation of proteins and for tanning. The tanning effect is much more effective than with other aldehydes, e.g. formaldehyde. Glutaraldehyde tans well also in an acidic medium. Also with glutaraldehyde the tane-ffect is better in an alkaline medium. The increase of shrinkage temperature is much faster than with other aldehydes. Leather tanned with glutaraldehyde has a special character. It is light and usable for garments and furs. It becomes very porous and as an aldehyde tanned product, it is wash and sweat resistant as the pH increases. The reaction of glutaraldehyde with collagen takes place better in a weak alkaline aqueous medium. Glutaraldehyde can also be used for simultaneous tanning with chrome-tanning agents and can be used to retan chrome-tanned or vegetable-tanned leathers.
Goatskin:- The skin from a mature goat, otherwise known as morocco, which has been vegetable-tanned and boarded. Produced in hard and soft grains. Hard grains may be either moss back or soft back. Soft backs require lining, hard backs do not. Carragheen moss when boiled produces a jelly and, when applied to the buffed flesh side, sticks down the fibres to give a smooth finish of uniform colour. Sizes vary from about 3½ sq ft, which would have a fine grain, to 10 or 12 sq ft, which would be coarse.
Goat accused of robbery
Police in Nigeria are holding a goat on suspicion of attempted robbery.
Vigilantes seized the black and white goat, saying it was an armed robber who had used black magic to transform himself into an animal to escape after trying to steal a Mazda 323.
A spokesman for the police in the eastern state of Kwara said: "The goat is in our custody. Vigilantes saw some hoodlums attempting to rob a car. One escaped while the other turned into a goat".
Daily Mail, Saturday 25th January 2009.
Guademici:- Guademici art was developed in Ghadames, a town in Libya. It involved punching, stamping, gilding and adorning a pure white alum-tanned hair sheep. The technology was taken to Cordoba in the 8th and 9th centuries, where it was developed and enhanced. "Well known are the skins that arrive white as snow and then leave here, tanned red, bearing your name, Cordoba" Latin Poem from 9th century.
Helvetia Leather:- Oil tanned hide from which not all the excess grease is removed.
Hogskin:- Leather made from the skins of wild animals living in Central and South America. There are two distinct types: the carpincho and the peccary.
Hide from a horse (a domesticated perissodactyl
mammal; in other words it has hooves with an odd number of toes), is the equal in
many respects of cowhide. At one time horsehide was a rare leather because it
could only be
taken from an animal that had died of natural causes. Now though it appears the
"natural death" horsehide law no longer exists. Still, most of the raw horsehide
used in US tanneries are brought over from France. Horse is by far the most
resilient of hides and is unlike any other leather. It it soft and supple but has an almost
"rubbery" quality to it. Horse hide is an extremely strong leather. It doesn't
stretch like deer and will outlast any cowhide. Horse hide has a strong and delicious
leather aroma. (See also Cordovan Here).
Horsehide - lizard print
Cowhide - suede
Kangaroo:- This hide is from
the Australian kangaroo or wallaby, the leather is strong and extremely
durable with a wide range of uses. The kangaroo is a macropod (macropod
literally means "big foot" and includes the wallabies, kangaroos, and their
close relatives. The main difference between the wallaby and the kangaroo is
in size — as measured by their feet!) native to Australia and is found
nowhere else in the world. It is a unique large herbivorous marsupial able
to hop long distances non-stop. There is absolutely no smell to a kangaroo
at any stage of life. In 1820, one Captain Phillip K. King recorded a
different word for the animal, written "mee-nuah". Thus
began the myth that Captain Cook had been mistaken about the name, "kangaroo",
and that what he had heard was a word meaning "I don't know" (presumably as
the answer to a question in English that had not been understood). Recent
linguistic fieldwork, however, has confirmed the existence of a word
gangurru in the northeast Aboriginal language of Guugu
Yimidhirr, referring to a species of kangaroo. What Captain King heard may
have been their word minha, meaning "edible animal". 1. Flanks and belly are usually scarred with tick
Izard:- Tufted leather, made from sheep skin splits or from sheepskin, whose grain has been removed by scraping and tanned by a process that involves the oxidation of oils in the skin of fish or marine animals, using these oils alone (tannage pure oil) or using a first aldehyde and then oils (combined tanning oil). The wild goat of the Pyrenees Mountains between France and Spain. Chamois-like antelope of the Pyrenees, 1791, from Fr. isard, Gascon isart, "perhaps of Iberian origin," or from Basque (cf. izzara "star").
2. The tail end of the skin is firmer than the neck end and often somewhat thicker than the neck end.
3. There is no line of weakness along the backbone, as in cowhide, but the centre of the back may have scars from barbed wire where the kangaroo has gone through fences.
4. Hard scars are new and weak. Flexible scars are fully healed and will usually be 80-90% of the original skin strength.
Horsehide - lizard print
Cowhide - suede
Kangaroo:- This hide is from the Australian kangaroo or wallaby, the leather is strong and extremely durable with a wide range of uses. The kangaroo is a macropod (macropod literally means "big foot" and includes the wallabies, kangaroos, and their close relatives. The main difference between the wallaby and the kangaroo is in size — as measured by their feet!) native to Australia and is found nowhere else in the world. It is a unique large herbivorous marsupial able to hop long distances non-stop. There is absolutely no smell to a kangaroo at any stage of life. In 1820, one Captain Phillip K. King recorded a different word for the animal, written "mee-nuah". Thus began the myth that Captain Cook had been mistaken about the name, "kangaroo", and that what he had heard was a word meaning "I don't know" (presumably as the answer to a question in English that had not been understood). Recent linguistic fieldwork, however, has confirmed the existence of a word gangurru in the northeast Aboriginal language of Guugu Yimidhirr, referring to a species of kangaroo. What Captain King heard may have been their word minha, meaning "edible animal".
1. Flanks and belly are usually scarred with tick
It is one of the strongest light-weight leathers available, and its fibres have a uniform orientation and an absence of sweat glands, giving it its inherent high physical properties e.g. tear strength, tensile strength and extremely good elongation performance. Furthermore, it does not require splitting, thereby avoiding any weakening of the leather as a result.
Also, its fibres run in a horizontal pattern, compared to bovine leathers which have a more vertical construction, thus imparting to it additional strength and high resistance to abrasion. This fibre structure and the specific tannages associated with kangaroo, also give it a natural resistance to water uptake.
Additionally, the skins contain much less natural fat than bovine hides/sheepskins etc, and they therefore require far less degreasing than other alternatives. The physical properties of kangaroo leather are therefore not impaired during tanning.
Skins:- Skins are measured in square decimetres (dm˛).
Ten square decimetres equal 1.076 square feet.
50 dm˛ skins are about 30 inches from neck to tail.
60 dm˛ skins are about 36 inches from neck to tail.
70 dm˛ skins are about 40 inches from neck to tail.
Utilization of the skin will depend on the project needs and skill of the cutter, as well as the characteristics of the individual skin. As a general rule of thumb assume 50% will be prime, with minimum stretch and even thickness, 40% good, and 10% waste.
Light Skins (under about 0.8 mm thick, 45-80 dm˛), Medium Skins (about 0.8 mm thick, 55 - 85 dm˛), Heavy Skins (about 1.0 mm thick, 55 - 85 dm˛).
Kangaroo leather gets crafted into remarkable creations, including kangaroo scrotums, which are functional for a variety of uses.
Kidskin:- This is chrome-tanned grain leather from a young milk-fed goat or kid, mostly of European origin. A fine tight grain skin, light in weight and durable.
Kipskin:- 1. A small cattle hide, i.e., the hides of fully mature cattle, other than the buffalo, native to the Indian Subcontinent and some parts of Africa, which are smaller than those of Europe and America. 2. The skins obtained from immature European and American bovine animals that have been grass fed and which are larger than calves but smaller than fully grown cattle. Among cattle hides, a kip is one weighing between 15 and 25 pounds in the green salted state. Generally, a kip is considered to be intermediate between a hide and a skin. Leather made from kips generally has a fine, tight fibre. 3. As an abbreviation of the full term "East India tanned kip" or "E. I. kip crust", a vegetable-tanned leather made from cowhide originating in the Indian Subcontinent and tanned in India, mainly in the south, and especially around Madras.
Different regions in India are famous for their
unique style and pattern of leather products. Rajasthan is known for its
decorated leather items. Bikaner and Jaisalmer produce decorative saddles.
Bikaner is also known for Kopi, a unique leather bottle made from camel
hide. In Rajasthan, beautiful lamp and lampshades are made from leather.
West Bengal is well known for its decorated leather products. These products are generally decorated with traditional designs and geometric patterns. Kashmir is also known for its ornamental leather products. Madhya Pradesh is popular for its embroidered red leather items. Gwalior, Indore, Bilaspur and Dewas are known for shoes, jutties, bags and mushks. In the state of Karnataka you will find leather products painted with epic and mythological pictures. These products are done in gold and silver. In some states like Andhra Pradesh, toys and puppets are made of leather.
Kosher Hide:– Hide of an animal which has been slaughtered according to Jewish religious custom by having its throat cut cross-wise; resulting in a different pattern of the hide sometimes referred to as a "cut-throat" or "stuck-throat".
Lambskin:- From a lamb or young sheep. Sold as whole skins only, about 3-10 sq ft depending on the age of the animal.
Laminated leather:- Has a coating greater than one third of the total thickness, but less than half.
Larrigan leather:- An American speciality made of light cattle-hide and used in the manufacture of the heavy moccasins worn by lumbermen to guard against slipping when walking on wet logs.
Latigo:- Cowhide. The un-split or grain split tanned with aluminium salts and gambier (an astringent resinous substance obtained from the leaves and stems of a rubiaceous, tropical, Asian woody climbing plant Uncaria gambir, of the madder family, which includes coffee and gardenia trees); normally yellow in colour. It is softer and waxier than vegetable-tanned leather. It contains catechu-tannic acid (22 - 50%) and catechin (7 - 33%), as well as varying amounts of vegetable acids and their salts, sugar, starch, cellulose, wax, oil, and mineral matter. The catechin is not identical with that of cutch ("Cutch" is the purified aqueous extract of the heartwood of the multipurpose tree, Acacia catechu Willd.).
|Wild growth of Acacia catechu in northern Thailand|
It is one of the condensed tannins and has a relatively high pH value and total salts content. Used alone, gambier produces a rather spongy leather; however, when used in combination with other tannins, such as wattle extract or myrabolans, it is well suited for both heavy and light leathers. In England, it has been used mainly for the tanning of calf and kip skins. Also known as "catechu", "pale catechu", and "terra japonica". Catechu is extracted from the heartwood of Acacia catechu, a leguminous tree of the pulse family, native to India and Myanmar. Catechu is a fast brown dye used for various shades of brown and olive, including the familiar khaki, and also in tanning. Dark catechu or cutch, which is mainly obtained as a by-product of the katha industry is marketed as small cubes or blocks, rusty brown or dull orange in colour and of conchoidal fracture. It is used only for industrial purposes, largely for dyeing cotton and silk and preserving fishing nets, sailing ropes and mail bags, also in water softening and the manufacture of stencil and printing ink.
Lizard:- Any of the vast numbers of the lizard family. Small reptiles are measured in centimetres across the widest section of the body for costing purposes.
Memel:- Black or brown curried hide leather, heavily embossed. Used for boot upper leather. Memel calf is dressed on the grain, and is not much used.
Merinillo unborn (Spanish "merinillo nonato"):- Tanned sheepskin and finished with a type of fine wool and fuzzy, made from the skin of a lamb or a lamb unborn.
Meter leather:- A speciality leather prepared from selected sheepskins in such a way as to make it airtight, and used for the measuring of gas meters.
Mocha Leather:- A leather made from any variety of hair sheep. After the grain has been removed by a liming process known as “frizing", the fine fibres below the grain are sueded. See “Suede" below. It is one of the finest of nap finished glove leathers.
Mocha Suede:- Arabian blackhead hair sheepskins (commonly called blackhead Mochas), it's chrome tanned and the grain removed by mechanical abrading rather than by hand frizing. It's suede finished on the flesh side. This leather retains most of the characteristics of the frized skin, particularly the fineness of finish, due to the closeness of the fibres of the skin. It's washable, and wears well.
Mukluk Leather:- Leather usually made from deer, elk, or similar skins. It is tanned white with formaldehyde, alum or syntans.
It is highly permeable to moisture vapour and retains its flexibility at very low temperatures.
(Syntans:- A contraction of "synthetic tannins", which are chemicals that combine with, or affect, the protein constituents of hides and skins and produce a product that is flexible, porous, and has the desirable qualities of leather. The most widely known syntans are made by treating aromatic substances, e.g., cresols, phenols, naphthalenes, etc., with formaldehyde and sulphuric acid. There are many variations in the ingredients of syntans, relative quantities used, and methods of manufacture. Syntans produce white or buff-coloured leather, depending on the ingredients, which darken upon exposure to light, and generally behave much like vegetable-tanned leathers. Although syntans do exist which can be used alone to produce leather (so-called exchange or replacement syntans), many syntans lack the filling power of vegetable tannins and produce an undesirably thin, "papery" leather. They are also more expensive than the natural tannins. Syntans do have desirable properties, however, and are widely used in both chrome and vegetable tannages. When used in conjunction with other tanning agents, where they are known as "auxiliary syntans" they perform the following functions:
1. the presence of 5% syntan helps dissolve solid vegetable tannin extracts and reduces any tendency to form REDS (condensed tannins) or BLOOM (pyrogallol tannins);
2. a pretannage with 5 to 10% syntan improves the shade, i.e., makes it paler, and the levelness of colour of a subsequent vegetable tannage;
3. a pretannage with a syntan or admixture with a vegetable tannage improves penetration of tannin into the skin;
4. when syntan is used with a vegetable tannin the leather develops a more uniform but paler colour upon being dyed, but the syntan generally prevents the development of deep, full shades.
Mule hide:- That is usually a chrome tanned split leather which is grey in colour. It is a very durable leather which withstands abuse. It is used for farrier aprons and as a horn wrap by cowboys to protect their saddle horns while roping.
Nappa:- A full grain un-split mineral-tanned sheep or lambskin, also goat or kid, and is soft and supple. A good all-purpose leather, it comes in many colours and is dyed throughout its thickness.
Niger:- The skin of the Nigerian goat or sheep, locally-tanned and finished by pretty basic methods using local material as a tanning agent. The skins are dyed to a yellow- or reddish-brown colour using natural dyestuffs.
Nubuck:- A very fine suede effect produced by abrasion of the grain surface. Nubuck leathers maintain the softness of naturally finished leathers while providing an incredible brushed feel. They will display all of the characteristics of natural leathers that have had their surface buffed. This nap, while very beautiful, means that nubucks are slightly more susceptible to spills and stains.
Offal:- This refers to the bellies, shoulders and cheeks of hides which are obtained by the "rounding" of the hide.