Niobium
On the label: Niobium · Metal
What it is
A grey refractory metal that can be anodized to blue, purple and gold without dye. Nickel-free and used for hypoallergenic ear wires and body jewelry.
Metals: Solid metals: what the piece is made of all the way through. Purity is written as karat (gold) or parts per thousand (925 silver, 950 platinum).
Wikidata: Chemical element with symbol Nb and atomic number 41. Q1046 →
In the research
70 PubMed papers mention it with jewelry, allergy, eyewear or UV; the three most recent:
- Reversible Symmetry Switching, Giant Birefringence, and UV Second-Harmonic Generation in Hybrid Niobium Oxyfluorides · Angewandte Chemie (International ed. in English), 2026
- Biosynthesis, characterization, and biofunctional assessment of niobium oxide nanostructures obtained using lactic acid bacteria-derived supernatants · Beilstein journal of nanotechnology, 2026
- Optical constants of Sc, V, Cr, Co, Ni, Nb, Mo, Rh, Pd, Hf, W, Re, Os, Ir, Pt, Au, and ZrO(2) in the extreme ultraviolet range · Optics express, 2026
A paper is a paper, not a verdict: titles are listed so you can read them, and a study on one fabric or one filter says little about the piece in your hand.
Pieces whose listing names it
1 on the siteMatched from the words in the supplier's listing; the full material line is on each product page.
Other metals
Clasp & Lens describes materials from the public record and does not appraise, grade or test pieces; what a listing states is the supplier's statement. If a piece causes a rash, take it off; a reaction that spreads or blisters is a doctor's question, and sunglasses are no substitute for impact-rated eye protection where that is required.