XRF readings:
Lead: 4949 ppm · Cadmium: 221 ppm · Arsenic: 14 ppm
Verdict: High: FluoroSpec test required
This Vintage Pyrex Honeydew Summer Impressions Custard Cup: 4,949 ppm Lead, 97 ppm Cadmium. 90 ppm Lead is unsafe for kids. tested at 4949 ppm lead, significantly elevated. The bioavailability question (can this lead reach a person?) depends on whether the lead is locked into a fired matrix or sitting on a painted surface. Cadmium reads 221 ppm, which is also flagged territory.
What this XRF reading actually means →
XRF measures lead presence on the surface. It does not measure whether that lead can reach a person. That distinction matters for how you should react to this number. Read the full primer.
Test your own dishes with FluoroSpec →
Source: EverythingLead · Test method: XRF (Niton XL 5 Plus, 1.5 sigma)
License: Verdict and methodology © EverythingLead, CC-BY-SA 4.0. Factual XRF measurements are not copyrightable (Feist v. Rural Tel., 499 U.S. 340).