Hematite
On the label: Hematite · Gemstone
What it is
Iron oxide, metallic grey-black and heavy, Mohs 5.5 to 6.5. 'Magnetic hematite' is a made ferrite, not the mineral.
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: Common iron oxide mineral (Fe₂O₃). Q103223 →
In the research
46 PubMed papers mention it with jewelry, allergy, eyewear or UV; the three most recent:
- Spectroscopic and geochemical fingerprints for chromophore identification and origin determination of Davdar emeralds from Xinjiang, China · Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy, 2027
- Synthesis and multi-technique structural characterization of trimetallic oxide nanocomposites for environmental and medicinal applications · Scientific reports, 2026
- Time-resolved chemically-selective spectroscopic investigation of the redox reaction between hematite and aluminium · Nature communications, 2025
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
3 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
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.