Materials glossary / Standard and mark
Ring size
On the label: Ring size · Standard and mark
What it is
The inside circumference of a ring, expressed as a US number (3 to 15), a UK letter or the ISO millimetre measure; the converter on this site maps them.
Standard and marks: The marks, tests and laws behind the words on a label: karat stamps, UV400, ANSI Z80.3, the FTC Jewelry Guides, Prop 65.
In the research
10 PubMed papers mention it with jewelry, allergy, eyewear or UV; the three most recent:
- A Semiflexible Tetrahydrazone Macrocycle for Binding of Pyrophosphate and Smaller Anions · The Journal of organic chemistry, 2024
- Dynamic single microparticle manipulation in the far-field region using plasmonic vortex lens multiple arms with a circular groove · Nanoscale advances, 2023
- The network structure of the corneal endothelium · The Journal of chemical physics, 2023
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
24 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
Other standard and marks
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.