Fluorite
On the label: Fluorite · Gemstone
What it is
Calcium fluoride in purple, green and bands, Mohs 4: a display and pendant stone, too soft for rings.
Gemstones: Natural gemstones, as mined and cut. Hardness (Mohs scale) says what scratches what; treatment (heat, oil, dye) must be disclosed under FTC rules.
Wikidata: Mineral, calcium fluoride. Q102151 →
In the research
20 PubMed papers mention it with jewelry, allergy, eyewear or UV; the three most recent:
- Initial Performance Evaluation of an Ultraviolet 157 nm Laser Ablation System for ICP-MS Analysis · Analytical chemistry, 2026
- The Synthesis and Photophysical Performance of a Novel Z-Scheme Ho(2)FeSbO(7)/Bi(0.5)Yb(0.5)O(1.5) Heterojunction Photocatalyst and the Photocatalytic Degradation of Ciprofloxacin · Nanomaterials (Basel, Switzerland), 2025
- Room-temperature high-power laser emission of erbium-doped fluorite crystals at 2.8 µm · Optics letters, 2024
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
2 on the siteMatched from the words in the supplier's listing; the full material line is on each product page.
Other gemstones
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.