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Horn Furniture of Herman Metz Article
The use of cattle horn added to a furniture surface is quite old. A French furniture maker, Andre Charles Boulle made use of horn, ivory, and brass as an overlay on furniture as early as the beginning of the seventeenth century. The process of cutting, shaping and flattening cow horns into thin sheets dates back to the time of the Romans.
Cattle horns are a protein matter called keratin, the same as our hair and fingernails. The outer horn that you see on an animal’s head actually covers a bony inner core that is a part of the animal’s skull and is held in place by a thin layer of sticky, fleshy membrane. When removed by natural drying or in boiling water, this outer horn is found to basically hollow and grows in layers of uneven thickness. It is most thin at the base and thickens to a solid tip.
There are at least two methods to produce horn veneer. In the 1700’s, European horn crafters would cut horn into various sized pieces, soaking it in hot water or oil for softening. (Horn becomes very pliable when subjected to heat, especially hot water.) The horn was then flattened, placed in wooden clamps or between hot iron plates treated with tallow, and pressed to the desired thickness. Another method was to put the pieces in boiling water. After a time, the layers would begin to separate, possibly due to the fact that there is a thin layer of liquid between them. These sheets of horn would then be flattened, allowed to dry, cut, shaped and fitted to a wooden surface, producing horn veneer. Allowing that the separated layers of horn are not identical in their thickness, it seems likely the craftsman would attempt to even the thickness of the cut pieces as much as possible before application. If he found any variance after application, he probably removed it by a light finish sanding to produce the desired smooth surface. This, of course, would depend on how near a perfectly-smooth surface the craftsman wanted. Not all veneering will be found table-top smooth. To date, I’ve seen two veneered pieces with uneven surfaces.
In its natural state, the horn has a rough surface After being softened in the hot water, this roughness can be scraped smooth with a straight-edged instrument. This scraping can be done before or after the horn is cut into pieces and, from my experience, it is much easier to sand or scrape the horn before cutting it. A final polishing produces a beautiful finish. In today’s world, machine sanding of a dry horn is common practice.
Also......
http://www.personal.utulsa.edu/~marc-carlson/horn/horng.html