Titanium for jewelry: grades and "implant-grade" explained

The short version

We work from documents and have not tested any jewelry. This page is narrower than its title suggests, and we would rather say so than fill the gap. The standards bodies’ own pages (ASTM, ISO) blocked us, so we cannot tell you what ASTM F136 or ISO 5832-3 actually specify, or how “grade 1 to 5” map onto them. What we can document is how makers use these labels, how PubMed abstracts name titanium grades, and what the regulator pages we read say about jewelry and about “hypoallergenic”. The full list of gaps is under what we don’t fully know.

What makers write

Three makers whose pages we read for our titanium earrings roundup use standard numbers, each in its own wording (maker pages captured 2026-11-13):

• Blomdahl USA lists “Pure Medical Grade Titanium ASTM-F67” for both the earring and its back.
• Impuria lists “F-136 ASTM Titanium” for a 16G (1.2 mm) post.
• Tini Lux lists “Pure Titanium ASTM F-67” as the base metal and describes the two numbers itself: “ASTM F-67: Pure, unalloyed titanium” and “ASTM F-136: Implant grade titanium (used for flat back studs)”.

Those are the makers’ statements. We did not see a certificate or lab report behind any of them, and we cannot confirm from a primary source that the descriptions match the standards. A listing that says only “implant-grade” or “medical-grade” gives you no standard to check. Two earrings in that roundup were left out for exactly that reason.

How grade numbers appear in the literature

PubMed abstracts we read use the grade numbering for commercially pure titanium without explaining it. A macaque implant study built an endoprosthesis from “commercially pure grade 4 titanium” (PMID 33272771). A metallurgy paper compares an experimental alloy against “CP-Ti Grade 1” (PMID 36676448). A machining study works on “pure titanium (Grade 2)” (PMID 36614453).

So grades 1, 2 and 4 are at least used as labels for commercially pure titanium in those papers. None of the abstracts says what distinguishes one grade from another, and none addresses Grade 5 or Grade 23, so we do not describe them. A grade number from a seller is a pointer to a specification, not a statement of how a piece will behave on skin.

Is there a legal meaning for “implant-grade”?

We found none in what we read. The CPSC’s jewelry FAQ says there are “no mandatory federal requirements specifically for jewelry”, and lists industry consensus standards instead: ASTM F2999 for adult jewelry and ASTM F2923 for children’s jewelry. We did not read either standard, so we cannot say whether they address titanium or any grade of it. Children’s jewelry must meet the requirements for children’s products, such as total lead content, per the same page.

On the neighbouring word, the FDA says of cosmetics that “there are no Federal standards or definitions that govern the use of the term ‘hypoallergenic’” and that it “means whatever a particular company wants it to mean”. That is a cosmetics page; we did not find a jewelry equivalent, and we treat the word on jewelry the same way: the maker’s own claim. Our guide on what “hypoallergenic” means and the one on hypoallergenic jewelry cover the term further.

Titanium is not a promise either

A grade label says something about the metal, not about your skin. A 2022 review says the most common metal allergens are nickel, chromium and cobalt, while “gold, palladium, titanium, and some others have also attracted attention”. A 2021 systematic review and meta-analysis, which included only three case-control studies, reports that titanium hypersensitivity is more prevalent in patients with titanium implants, and also describes titanium as widely considered to have good biocompatibility, thanks to a passivating titanium dioxide layer that forms in air.

A 2019 review of implant allergy says allergic responses to surgical implants are infrequent, and notes that cardiac stents and patches are often made of Nitinol, “a composite of nickel and titanium”. That is a medical device, but it is a reminder that the word “titanium” on a product does not by itself tell you nickel is absent. Another review recommends asking surgical patients about cosmetic jewelry problems beforehand and says titanium or carbon fibre implants should be used if a metal sensitivity is known. These abstracts concern implants in the body, not earrings, and we draw no conclusion about jewelry from them beyond the points above.

Medical questions, including whether you react to titanium, belong with a dermatologist or an allergy society.

What else to check on a listing

• Coatings. Makers we read list the coating separately from the base metal. Tini Lux says titanium nitride PVD is applied to give an 18k gold colour; Impuria describes titanium PVD gold plating. See PVD-coated jewelry.
• Backs and other parts. The post may be titanium while the back is something else. Blomdahl USA states its back material; not every maker does.
• The alternatives. Titanium vs stainless steel, surgical steel, niobium and platinum are covered separately.
• Nickel basics. Start with nickel allergy and jewelry and the EU nickel rules; for ear and nose piercings see earrings for piercings and nose piercing jewelry.

What we don’t fully know

We could not open the ASTM, ISO or Association of Professional Piercers pages, so every statement about what F136, F67 or ISO 5832-3 require is missing from this page on purpose. We found no definition of “implant-grade” for jewelry, which is different from proving none exists. We read abstracts, not full papers, and most concern implants rather than jewelry. The rest is listed under “unknowns” on this page.