When tested with an XRF instrument the small burnt orange Franciscan potteries dish (made in California) pictured here had the following readings on the FOOD SURFACE of the dish:
- Lead (Pb): 228,400 +/- 8,600 ppm
- Barium (Ba): 2,765 +/- 437 ppm
- Chromium (Cr): 398 +/- 212 ppm
- Tin (Sn): 62,800 +/- 2,400 ppm
- Zinc (Zn): 535 +/- 55 ppm
- Copper (Cu): 296 +/- 123 ppm
- Iron (Fe): 593 +/- 138 ppm
- Vanadium (V): 1,546 +/- 629 ppm
This dish was tested for a full three minutes (180 seconds) to make sure to have the most accurate possible reading.
I will update this post with more information shortly, but in the meantime – please read some of the other posts I have written about vintage dishware to better understand the test results reported on this website.
As always – thank you for reading and for sharing my posts.
Please let me know if you have any questions.