- Should be able to withstand the heat and pressure of autoclave sterilization.
- Should be inert and compatible with the body so it doesn’t cause irritation, allergy, or infection.
Mill test certificates (or “mill certs”) are documents that provide evidence of a specific grade of metal with an ASTM or ISO code designation. These are provided to jewelry makers by the manufacturers of the raw materials. Some jewelry companies also have biocompatibility testing done by independent labs. Your piercer may have copies of these certificates available for you to review. You don’t need to understand what the numbers mean, but the document should warrant that the metal is one of the grades listed below. It is not possible to know whether the piece of jewelry you’re buying is from the batch indicated on the paper, but the presence of documentation listing the appropriate materials means that your piercer is more likely to be purchasing from reputable sources and is conscientious about their jewelry quality.
- Surgical Steel is made of a variety of alloys. Many of them are used for body jewelry, but only a few specific grades are proven biocompatible: steel that is ASTM F-138 compliant or ISO 5832-1 compliant; ISO 10993-(6,10, or 11) compliant; or (EEC [European Economic Community] Nickel Directive compliant.)
- Titanium is a lightweight metal that is ideal for people with concerns about nickel sensitivity. This material can be anodized to create jewelry of different colors without affecting the safety. Look for implant certified titanium (Ti6Al4V ELI) that is ASTM F-136 compliant or ISO 5832-3 compliant, or commercially pure titanium that is ASTM F-67 compliant.
- Niobium has been widely used by piercers with good results for many years. It is very similar to titanium, but does not have an implant-grade designation. Like titanium, niobium can be anodized to produce different colors. (And, unlike titanium, it can be heat treated black.) Anodized niobium and titanium may fade due to body chemistry or when worn in friction-prone areas, but this is not harmful.
- Gold (yellow or white) is appropriate for initial piercings if it is 14k or higher, nickel-free, and alloyed for biocompatibility. Gold higher than 18k is too soft for body jewelry because it can easily be scratched or nicked. Gold plated, gold-filled, or gold overlay/vermeil jewelry is not acceptable for fresh piercings. All of these involve coating a base metal with a layer of gold. The gold surface (which is very thin—measured in millionths of an inch) can wear or chip off.
- Platinum is a heavy precious metal that is extremely inert and excellent for wear in body piercings. However, body jewelry in this material is rare and very expensive due to the high cost of the material and greater difficulty in manufacturing jewelry from it.
- Biocompatible polymers (plastics) including Tygon® Medical Surgical Tubing S-50HL or S-54HL, PTFE (Teflon®), or Bioplast™ are considered suitable for new piercings. Tygon is a bio-compatible medical tubing that is highly flexible. It should be changed every few months as it stiffens and discolors from extended wear. PTFE, a white plastic, is widely accepted within the industry. Bioplast was created specifically for piercings and is similar to PTFE, but comes in an array of colors and shapes. These may be worn as a substitute for metal jewelry. With new polymer products coming into the marketplace, check that the product you are purchasing, if not listed above, is USP VI compliant. These can be sterilized in an autoclave.
- Glass—Fused quartz glass, lead-free borosilicate, and lead-free soda-lime glass are inert and considered safe for initial piercings. They can also be sterilized in an autoclave.