Materials science

2nd Skin materials science


Titanium is the wonder-metal of the modern age, with multiple fascinating characteristics. It is particularly light and biocompatible and therefore well suited to the needs of piercing. Those suffering from allergies can rest easy knowing that titanium used at 2nd Skin is nickel-free. The quality of the titanium is always to be scrutinized as not all qualities of titanium should be used for earrings. At 2nd skin, all of our earrings are produced from Grade 23 titanium (Ti6 AL4V Eli), the quality with the optimum characteristics for earrings.


Since its introduction by the medical industry in the late 80’s, PVD (physical vapor deposition) has been widely used. The procedure results in a thin, abrasion-resistant layer on the surface of objects (e.g. medical instruments and implants, including pacemakers, surgical instruments, and orthopedic implants) by exposing them to a gas phase (plasma). During the PVD process, the surface of the substrate (titanium in our case) develops a tough, non-stick, abrasion-resistant sheath. The main advantage of the PVD technology lies in the ability to modify the characteristics of the surface of a substrate without adversely affecting the characteristics or biomechanical functionality of the underlying material. The biocompatibility of the PVD layer is a requirement for its use in surgery and medicine. The PVD process and resulting surface layer has been analyzed by independent, external laboratories and its biocompatibility has been certified for use used in medical instruments and implants that come into contact with bones, skin and other bodily tissues. Moreover, multiple specialists and experts recommend Blackline for use in body piercing. It is universally considered safe (BIO-SAFE) and unproblematic.

Anod / Anodized / Titan 6AL-4V-ELI (Grade 23)

Titanium (Grade 23) is the ideal material for both new and existing piercings. It’s nickel-free and compliant with the 2001-introduced EU nickel guidelines. Grade Ti6AL-4V-ELI is surgical grade titanium used in medicine since the 1950s, which can be either polished or anodized. Titanium is double the strength of steel with only half of the weight.

Stainless steel

Stainless steel (316L) has a wide variety of applications in medicine, including use as screws, pins and plates for bone fixation, as prostheses, threads, clamps and clips, and as heart pacemaker electrodes. Stainless steel (grade 316L and 316-LVM) is well suited for secondary applications (i.e. after complete healing of a piercing). Stainless steel is not recommended for primary applications (i.e. new piercings).


White or yellow gold must be properly alloyed to make it biocompatible. For primary applications (i.e. new piercings), 18 Karat gold, also called 750-gold (i.e. 75% gold), is used. The non-gold component must of course be biocompatible. However, gold jewelry has the potential to cause allergic reactions or inflammation. The quality of 375- (37.5%) and 585-gold (58.5%) are not nearly as high as 750-gold. For new piercings, the laws and guidelines require use of sterilized gold with a maximum nickel content of 0.05% by mass.

Zircon Line

Gold zirconia PVD (Physical Vapour Deposition) is a thin, abrasion-resistant layer on SS316L piercings.


Silver is not suited for use in new piercings, but is generally fine for well-healed existing piercings as long as it is genuine sterling silver (925-silver, or 92.5% silver). Sterling silver is comprised of 92.5% silver and 7.5% copper, and therefore no problem with respect to allergic reaction against nickel. Rarely, however, individuals can also exhibit allergic reactions to silver. In addition, in contrast to gold, silver has a tendency to become tarnished overt time, and in some instances can even become black..


Polytetrafluoroethylene (PTFE), better known as Teflon, is a synthetic fluoropolymer of tetrafluoroethylene with characteristics that make it well suited to use in piercing, in particular long-term placement under the skin. PTFE has an extremely smooth, non-stick surface which is particularly resistant to attachment. In addition, aggressive substances (e.g. in the mucous) don’t affect PTFE, which is particularly important for use in mucous membranes (e.g. in the mouth cavity). In medicine, PTFE is often used in replacement blood vessels for middle ear infections or even for face corrections.

Rose Gold

Pink gold PVD (Physical Vapour Deposition) is a thin, abrasion-resistant layer on SS316L piercings.