Jewelry Materials

Bamboo is not a wood but a grass. Several thousand different species exist, ranging from tiny plants to huge towering trees. Many species are light yellow, tan, or green; some can be purplish or black. Most species are solid in color; some can be striped or spotted.

Bamboo stalks are hollow and segmented with solid portions of culm. Bamboo is lightweight; its cross-section may be round, oval, or slightly cardioid (heart-shaped). The outside of the bamboo is naturally smmoth and protective and should not be removed to make plugs. The inside is normally whitish and may have a papery lining which is usually removed or is shed over time.

Hardwoods are most often used to make plugs for enlarged piercings, such as ear lobe, labret, and septum piercings. Hardwoods are natural materials that work in harmony with the body. They can "breathe" with a piercing and allows an interchange of oils. Wood stays warmer than metals. Wood does not develop the bad odor plastics can develop.

Hardwoods are broad-leafed, deciduous trees (angiospermous). The term "hardwood" does not actually refer to hardness: for example, balsa is a hardwood. The part of the tree normally used is the center heartwood, normally darker and denser than the surrounding sapwood.

A few species of wood commonly used for jewelry, furniture and inlays are endangered or threatened. These species are regulated by CITES, the Center for International Trade of Endangered Species. Endangered species include Brazilian rosewood (Dalbergia nigra). Threatened species include Mexican mahogany (Swietenia humilis) and Carribean mahogany (Swietenia mahagoni), Commoner (Guaiacum officinale), and Holywood lignum vitae aka "Tree of Life" (Guaiacum sanctum), Bigleaf mahogany (Swietenia macrophylla), and American mahogany (Swietenia meliaceae). In some cases, wood from threatened species is acquired by salvage or through sustainable harvesting. Grain (fibers within the wood) is considered either open or closed. Open-grained woods may collect bacteria, shed skin tissue, and dirt and hence generally should not be used for jewelry.

The overall shape and dimensions of the piece should be consistent and appropriate for the particular piercing with room to allow for possible swelling. The finish should be free from scratches, pits or tool marks. The piece should be free of raised grain (wood fibers), even when wet. Luster varies from species to species and the wood may or may not shine. An oiled plug will appear dull.Because hardwoods are porous and readily absorb and release moisture, oil, and bacteria, hardwood plugs are best worn in healed piercings and dry areas of the body. Because hardwood jewelry cannot be sterilized it should always be handled by clean hands and only worn by one person. Autoclaving hardwood jewelry may cause it to crack, split, and warp. Hardwood jewelry should be cleaned regularly with a non-chemical soap that is safe for the body. Tea Tree oil can also be used; prior to use a patch test is recommended to test for allergy. Hardwood jewelry should be oiled after cleaning to benefit the skin and aid insertion.

The type of finish applied is usually an oil and sometimes a sealant. Many finishing oils and sealing products contain chemicals, toxins, solvents, petroleum or animal products, or pigments. Using a finish that entirely seals a hardwood plug eliminates the purpose of wearing wood. I usually recommend a non-toxic oil or wax. Food grade oils such as olive and peanut are generally safe but may break down (turn rancid) with heat and time; pieces finished using food grade oils should be washed and re-oiled periodically to avoid turning rancid. Waxes can be animal or vegetable based; waxes may come off with heat or be rubbed off while cleaning. I do not recommend using pigment as most are chemical or solvent based and can fade or enter the bloodstream.

Some people are allergic to certain hardwoods. A sensitivity to hardwoods can also be acquired with exposure. The risk of developing a sensitivity to certain hardwoods is increased for those who work with the woods by way of the dust which is produced in the production process. The hardwoods likely to cause allergic reactions include all woods within the Dalbergia genera, or the rosewoods: African blackwood (Dalbergia melanoxylon), Brazilian rosewood (Dalbergia nigra), Cocobolo (Dalbergia retusa), Indian rosewood, aka Bombay blackwood (Dalbergia latifolia), Kingwood aka Violetwood (Dalbergia cearensis), Tulipwood (Dalbergia frutescus), Teak (Tectona grandis), Purpleheart aka Amaranth (Peltogyne spp.); and possibly Greenheart and Satinwood (Chloroxylon swietenia). Some woods may be very hard to identify; for example, African blackwood can masquerade as ebony.

All of these materials are somewhat porous and readily absorb moisture and skin oils. This can lead to cracking in a few of these materials. Absorption of moisture can be avoided by coating or pressure impregnating the material with a substance such as bee's wax or a hypoallergenic sealant. I would not recommend oiling ivory or horn jewelry as it will tend to promote cracking rather than deter it.

Skin oils make these materials more flexible. With designs such as the captive bead ring, this can result in lost beads if the carver does not adjust for expansion. I recommend using a coating or some type of pressure treatment to prevent the ring from becoming flexible. Untreated captive bead rings should be very tight before they have been worn. If you are afraid of breaking an untreated ring you should wear the ring without the bead for about a day to soften the ring.

Dall sheep horn is semi-transparent material with an opaque white grain. The advantage of sheep horn is its superior flexibility over other organic materials. Sheep horn tends to distort or bend when exposed to moisture or skin oils. Body jewelry that must to hold a precise shape or is dependent on tension, like a captive bead ring, must be stabilized.

Mammoth ivory is easily acquired in Alaska, Siberia and other places where it has been preserved underground in permafrost for thousands of years. Gold miners often find it during erosion mining in glacial silt. Because of it's age mammoth ivory is difficult to acquire in large solid pieces. Ivory is softer than most stone and is flexible which makes it ideal for intricate and delicate carvings. The foremost disadvantage of using aged or fossilized ivory for body jewelry is that it absorbs skin oils which causes it crack. Mammoth ivory ranges in color from a cream white to a medium brown. Darker ivory is more fragile and will crack with moisture much more easily, making it unsuitable for delicate work.

When polished, water buffalo horn looks similar to ebony. It is not as flexible as sheep horn and has a much stronger grain, which makes delicate or detailed work more difficult. Because of the grain it will crack with exposure to skin oils and thus cannot be used for body jewelry unless stabilized.

Most sources of fresh ivory such as elephant tusks are subject to legal restrictions. Two sources of unrestricted ivory are warthog and hippopatumus tusks. Fresh ivory does not have the same problems with cracking that aged ivory has.

Antler varies in color from ivory white to shades of brown and gray and sometimes has a purplish hue near the surface. White antler can be nearly indistinguishable from ivory in appearance. Antler will almost never crack with exposure to moisture or skin oils. It is an excellent substitute for ivory because of its comparative cost, availability, and durability. However, it is a bit softer and more porous than ivory, resulting in less strength against fractures.