All About Pocket Knives

IVORIES

Kinds of Ivories include Elephant (both African & Asiatic), Mammoth , Hippopotamus, Walrus, Whale, Warthog and Boar. Elephant and Mammoth ivories are distinguished by a peculiar structure in the grain properly called Schreger lines, and referred to as cross-hatching, engine turned effect, or stacked chevrons. Whether this structure is seen depends upon the direction of cut of the elephant or mammoth ivory. Some ivories have a grain, best described as similar to tree rings in miniature. How, and where they appear on a piece of jewelry, depends upon the angle of the cut. Wonderful technical information for separation of one ivory from another can be found at this website U S FISH and WILD SERVICE., along with some really good pictures of crosshatching and graining. The graining may become more obvious with time and patina. Spacing of graining and straightness of graining is uneven, somewhat like strips of bacon, in miniature.

IVORIES IN JEWELRY

Elephant Ivory is probably the most commonly used ivory in jewelry, both costume and fine. Its most distinctive feature, if it can be found, is crosshatching (specimen at 300X). A bangle bracelet will usually show crosshatching on at least two small sections, however, many pieces of elephant ivory will not show any crosshatching because of the angle of cut through the material, though you should be able to find some grain lines. Mammoth ivory is the only other ivory that shows the crosshatching, seen extremely clearly in this example.

Elephant ivory varies in quality and in color, depending first upon the type of elephant, but also upon the region, and the age of the ivory. Color ranges from a dead white to soft yellowish, to pale rosy white, and into the brown tones. Luster is from greasy to dull. Quality African ivory will take a high polish.

Mammoth Ivory, from prehistoric animals will range in color from soft creamy to a warm brown and even dark brown. The outer parts of a mammoth ivory is sometimes fossilized by ores, though the interior will remain the same, and when this occurs that outer area will then be blue or green, and may remind you of intensely colored opals, or look a bit like abalone in coloration.

Hippopotamus ivory - One source indicates the grain is closer and denser than elephant ivory and a a pure white with a texture that has been described as between elephant ivory and pearl shell. Another source describes it as having no grain pattern and being very homogeneous. There are apparently characteristics in larger pieces of this ivory that may allow precise identification as hippopotamus.

Walrus ivory - often used for sword handles in its original form. Scrimshawed by sailors of old. Probably the second most commonly seen ivory as I believe it is what the Eskimos were/are using. Color is a yellowish cream. Prehistoric Walrus ivory is seen in the current marketplace. There are apparently characteristics in larger pieces of this ivory that may allow precise identification as walrus.

Warthog ivory and Boar Ivory -

IVORY SUBSTITUTES

Currently, there are a lot of scrimshawed things out there made of resins & other materials to simulate ivory, some of them extremely believable. Earlier in this century (in jewelry and small accessories) we had celluloid, Ivorine, etc., things that looked at bit like ivory in that they had lines in them that simulated the grain of elephant ivory. Most of these will have lines that are too straight, too even, and will continue down the ends and on the other side with no variation .

Bone: Bone has tiny little channels where the blood vessels and nerves resided. You can often see these, either straight in (on the backside) looking like little pockmarks, or as lines at an angle almost perpendicular, ie "dots and dashes". It can be easy to see, but also sometimes is not apparent on the surface, however, if you put a light behind it (lay it on your scanner) you should detect the short little lines of the channels. Bone will usually be curved (concave) on the back because the bone was hollow, however it can be flat on the back. Elephant ivory in jewelry will usually be flat on the back (pendants & brooches).

Vegetable Ivory - (not an ivory) Corozo nut and also the doum-palm nut. Grandpa Spragg has a wonderful information page about the Tagua nut and examples of his carving. Just click on his link about "Research of the Tagua" The characteristics are the same as hippo ivory and separation of the materials is difficult.

CAUTION: I have seen bone or other materials that were lightly brushed with a sienna color dye, giving an impression of patina and simulating, but not closely, the grain of ivory.

TIP: Search for the ivory graining and crosshatching under a strong light & magnification, turning the piece at various angles. The difference in translucence in the layers of lines will often show up under these conditions. Bone may reveal its blood vessel channels when lighted from below.

ANTIQUE IVORY SUBSTITUTES: Ivory and ivory substitutes were fashionable around 1850. Substitutes included bone, clay, porcelain & celluloid. The porcelain, which hasn't survived well, was often parian (seems to be the same as Belleek), preferred for its glaze. I can't say if the porcelain was carved or molded, but would suspect the latter.