Gold
On the label: Gold · Metal
What it is
A soft yellow metal, element 79. Pure (24k) gold is too soft for daily wear, so jewelry gold is an alloy; the karat number says how many parts in 24 are gold. It does not tarnish or corrode and is one of the least allergenic metals.
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 Au and atomic number 79; a dense, malleable, and corrosion-resistant precious metal widely used as currency, in jewelry, electronics, and as a financial reserve asset. Q897 →
In the research
4,473 PubMed papers mention it with jewelry, allergy, eyewear or UV; the three most recent:
- Machine-Learning-Assisted Risk Stratification for Tuberculosis Infection in High-Risk Groups Receiving Immunosuppressive Therapy · Diagnostics (Basel, Switzerland), 2026
- Keratoconus - Common, yet uncommon · Acta ophthalmologica, 2026
- Gold nanocluster-enabled nanobody-based fluorescence immunoassay for sensitive detection of β-lactoglobulin in dairy products · Talanta, 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.
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.