When such a stamped sheep skin is new on a book, and finished with gold, no one would for a moment suspect its genuineness, but if in skin form, the back of the leather will at once betray it. Real morocco has a hard close grain, but the back of the imitation will show a loose soft texture. Other leathers are imitated in the same way: pig skin, lizard skin, and others; and although there has been, and still is, much of such imitation used in the matter of bookbindings, there is still more of it used in the furniture trade.
But putting aside these base uses of sheep skin, it has a very fair record to show on its own unaided merits. Many early Italian bindings, good ones, were made in sheep skin; certainly it has not lasted well, but no doubt when new it was pleasing enough. In England, many of the early fifteenth century panel stamp bindings were made in sheep skin, not quite satisfactory now, but also probably well enough when new.
It is impossible to say much in favour of modern roan, the trade name for sheep skin, which has suffered badly at the hands of the tanner and the dyer; also probably the binders have not been without fault, as in order to get the leather flexible for joints and bands they have acquired a pernicious habit of paring it too thin, and another, equally hurtful, of unduly pulling and stretching it so that the fibres, or what is left of them, get strained and broken.
Skiver is part of a split sheep skin, the surface of which is altogether artificial. It is much used for cheap pamphlet bindings and looks well for the moment, but is not so strong as good paper. It is wonderful how cleverly the “paste grain” or artificial surface of skiver is made; it deceives most people easily. The remaining part of a split sheep skin is prepared quite differently and is made into “chamois” leather. Although this is not used for actual bindings, it is often enough made into linings for loose covers of fine books. It does well for this purpose, but must be kept in a very dry place as it has a certain affinity for damp.
The finest of all leathers for binding is goat skin, morocco as we now call it, from the reputed land of its origin. “Levant morocco” is still the name of the finest skins. Goats, however, have of course been common enough all over the world for ages, and so we find very ancient bindings in goat skin, quite possibly the most ancient, although I rather incline to vellum in this connection.
Many of the English twelfth to fourteenth century blind tooled bindings are in goat skin, tanned brown, most likely with oak bark, and from that period until now it has always been used here, at some periods more than others.
Goat skin always shows small hair dots in groups all over its surface; it is not quite smooth like calf, and also it shows certain structural striations. In early goat bindings both these marks show clearly, and until the time of Roger Payne in the eighteenth century, the leather was left in its natural state so far as surface marks went.
Italian bookbinders at an early date saw the beauty of natural sunk lines on goat skin, and accentuated them by rubbing in gold leaf. On such bindings the markings on the leather show as fine gold lines; it is a pretty idea, and can often be found on sixteenth century bindings, especially on those that were made for Tommaso Maioli.
French morocco bindings are frequently stained with colour, particularly those which were made about the time of Henri II. in the sixteenth century. The stain is usually put on the fillets or arabesques surrounding a central oval, in which is often a painted coat-of-arms. But as a rule such coloured bindings are in calf, which takes stain more easily than morocco.
Goat leather has never been so much liked by German binders as calf or pig skin. This is partly due to the fact that German bindings are as a rule ornamented with blind tooling, and goat skin is never satisfactory when treated in this way: its grain is against it; but for gold tooling, which has been brought to its greatest perfection by Italian, French and English binders, there is nothing that gives so fine a result as goat leather.