Copper
On the label: Copper · Metal
What it is
Element 29, a soft reddish metal. Worn on its own in bracelets and used in most gold and silver alloys. Reacts with skin acids to leave a green mark on some wearers; this is harmless but shows the metal is not plated.
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 Cu and atomic number 29. Q753 →
In the research
1,953 PubMed papers mention it with jewelry, allergy, eyewear or UV; the three most recent:
- A dual-function Cu-MOF-polyaniline nanorod composite for efficient water splitting and enhanced capacitive energy storage · RSC advances, 2026
- A binuclear copper enzyme platform for enantioconvergent radical (pseudo)halogenation · Nature chemistry, 2026
- Siloxane-Radical Species: Chemical Characteristics and Use for Mass Calibration in Aerosol Mass Spectrometry · The journal of physical chemistry. A, 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
8 on the siteMatched from the words in the supplier's listing; the full material line is on each product page.
Made in the USA
Made in the USA
Made in the USA
Made in the USA
Made in the USA
Made in the USA
Made in the USA
Made in the USA
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.