Materials for Piercings and Body Jewelry
Metals & Alloys

Metals are selected based on their biocompatibility and mechanical properties, such as malleability and hardness. In all cases, portions of the jewelry that are within the pierced body part need to be smooth, highly polished, and free from scratches. It's very important to know the specifics about the metals, since even nonreactive metals made from pure elements (e.g., titanium, niobium) may be made unsuitable by various treatments. For alloys (e.g., karat gold, steel), it's vital to know about the metal composition as well as any treatments applied to the material. Here's a list of metals that are used for piercings and body jewelry, providing their composition and treatments are acceptable:

• Stainless Steel
• Gold
• Titanium
• Niobium
• Platinum and related metals (palladium, iridium, probably rhodium)
• Silver

Here's a list of metals that can't be safely used for body jewelry:

• Pewter
• Brass or Bronze
• Any Plated or Filled Metal
• Non-Stainless Steel
• Most alloys containing a metal other than those from the first list (e.g., colored golds, sterling silver)
• Pretty much any elemental metal not listed in the first list. Examples include tin, nickel, aluminum, chromium, lead, cadmium, etc. It's not advisable to use copper, zinc, or iron, because these elements are reactive even though they tend not to cause problems with toxicity. The other metals on the 'do not use' list either provoke sensitivity reactions in some people or else have undesirable mechanical properties. Many metals are highly toxic and can be absorbed into the body across the skin.

Closer Look at the 'Approved' Metals

• Stainess Steel

  Really, this should read 'implant grade stainless steel', since 'surgical stainless steel' isn't a defined term and 'stainless steel' encompasses a lot of alloys which shouldn't be used for jewelry. The implant quality stainless steel alloys are ASTM F-138 (316L/LVM). 316L is a low carbon variation of alloy (hence the 'L'). 316LVM is vacuum melted (VM); a process which prevents airborne contaminants from being incorporated in the metal. 316LVM is slightly more desirable, but the vacuum melting is usually not necessary for healing and maintenance of piercings. Stainless steel contains sensitivity-provoking metals, such as nickel, but the steel develops an self-sustaining oxide coating which protects the body from all but the slightest exposure. This steel is hypoallergenic, but non non-allergenic: rare individuals may experience a reaction. The alloy is white, like silver, rather than gray like most other steels. The alloy is available over a range of hardness. Softer steel is more pliable and easier to insert, yet easier to scratch than harder steel. Steel that is too hard is difficult to bend and is liable to fatigue and develop fractures or break, so an intermediate level of annealing is desirable.

• Gold

  'Gold' as it is used for jewelry is an alloy, rather than the pure element. The metals alloyed with gold make it unsuitable for fresh piercings or even for healed piercings for some people. Others are able to tolerate karat gold that is at least 14 karat (58.3% gold). Some people are able to tolerate 18k gold (75% gold) in fresh piercings. The karat gold must be a solid alloy, not gold-filled or gold-plated, which can wear away to base metal with body friction or fracture from the bending associated with insertion. Metals which are alloyed with gold in karat gold include nickel, silver, zinc and copper. White gold may be more likely to produce a reaction than yellow gold because some white gold gets its color from a relatively high percentage of nickel. On the other hand, white gold which is produced by alloying gold with palladium is unlikely to provoke a reaction and can be worn by some persons who cannot tolerate implant-grade stainless steel. Green or pink gold is unsuitable for body jewelry because of appreciable concentrations of copper and zinc used to produce the colors.

  Some people will experience blackening of karat gold due to a reaction between acidic body fluids and the base metals in the alloy. Gold jewelry which is exposed to urine over a long time will become dull and rough. The gold can be buffed to remove buildup and restore luster. Exposure to povidone iodine, steam autoclaving, or sterilization tape will cause discoloration which can be remove using a soft buffing cloth. If the jewelry is pickled prior to use (surface depletion: heating the jewelry or submersing it in a weak acid to remove oxidized atoms of base metal bear the surface) then the jewelry will be less susceptible to discoloration.

• Titanium

  Titanium is a lightweight metal, usually encountered in an alloy rather than in elemental form. The alloy most often used for body jewelry is 6AL4V, specifically titanium ASTM 136 grade, which has low concentrations of interstitial elements. The titanium alloy should be highly polished to prevent ingrowth of body tissue into the pores of the metal. Although this alloy contains aluminum and vanadium, the titanium reacts with oxygen to form an inert oxide layer on the surface of the metal (similar to that formed by chromium in stainless steel). The oxide layer protects tissues from exposure to the aluminum and vanadium. In addition to polished titanium (light to medium gray), colored titanium is available. The colors are obtained via anodization, in which an oxide layer is formed on the metal surface. The thickness of the coating determines the color. The coating will wear away, so the color is susceptible to change and fading. Black metal is obtained by coating titanium with titanium carbide using physical vapor deposition. The titanium carbide is not biocompatible and black titanium is not suitable for use in body jewelry.

• Niobium

  Niobium is an elemental metal with a low reactivity that rarely causes sensitivity reactions. The metal is strong and flexible and somewhat heavier than 316L stainless steel. Niobium is available with a polished finish, matte (satin) finish, or anodized color finish. Niobium is porous and difficult to polish. Poorly polished niobium may retain residue of the polishing compound (often toxic). Matte finish niobium is not suitable for fresh piercings, as the roughened surface allows for adhesion to skin and provides a substrate for bacteria. Anodized colors are achieved by submerging the metal in an electrolyte solution and applying a voltage to create an oxide layer on the jewelry. Different colors are obtained by varying the thickness of the coating, which refracts light. The anodized coating is subject to wear and friction, so it will fade or change over time. Black niobium is made by heating niobium to red heat and then cooling it. The black metal can be polished and will not fade over time.

• Platinum Metals

  Platinum and other metals in the platinum group (e.g., palladium) will not elicit reactions with body tissues, but they tend to be heavy and costly. These metals are most often encountered in alloys with other metals (e.g., in karat gold)

• Silver

  Sterling silver is 92.5% silver that has been alloyed with another metal, usually copper. Sterling silver and fine (elemental) silver are tolerated by some people in healed piercings, but silver is unsuitable for new or unhealed piercings or for healed piercings in moist body parts, such as the mouth or genitals. Sterling silver tarnishes quickly and may react to cause a permanent graying of the skin. Although fine silver doesn't tarnish, it is a very soft metal, prone to scratches which can irritate skin and harbor bacteria.

• Overview - Materials for Piercings & Body Jewelry
• Metals & Alloys (Steel, Gold, Titanium, etc.)
• Non-Metals (Acrylic, Glass, Teflon, etc.)
• Natural Materials (Bone, Wood, Ivory, etc.)

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