When tested with an XRF instrument this brown ceramic mug with light blue glaze (“Made in China” and purchased at World Market in November of 2019 for $3.99) had the following readings:
XRF test focused on unglazed brown ceramic base of cup:
- Lead (Pb): 39 +/- 14 ppm (safe by all standards)
- Chromium (Cr): 1,605 +/- 100 ppm
- Zinc (Zn): 98 +/- 22 ppm
- Copper (Cu): 125 +/- 37 ppm
- Iron (Fe): 12,100 +/- 500 ppm
- Bismuth (Bi): 130 +/- 17 ppm
- Vanadium (V): 287 +/- 36 ppm
- Titanium (Ti): 850 +/- 69 ppm
- Zirconium (Zr): 7,857 +/- 193 ppm
- Platinum (Pt): 115 +/- 43 ppm
Note: area with white painted logo had similar readings to bare unglazed area.
XRF test focused on exterior glaze on rim of cup:
- Barium (Ba): 139 +/- 69 ppm
- Zinc (Zn): 73,500 +/- 2,100 ppm
- Copper (Cu): 266 +/- 59 ppm
- Iron (Fe): 1,990 +/- 207 ppm
- Titanium (Ti): 12,500 +/- 600 ppm
- Zirconium (Zr): 3,595 +/- 130 ppm
XRF test focused on glazed interior of cup:
- Zinc (Zn): 67,700+/- 1,900 ppm
- Copper (Cu): 273 +/- 58 ppm
- Iron (Fe): 2,549 +/- 230 ppm
- Titanium (Ti): 11,300 +/- 600 ppm
- Zirconium (Zr): 4,376 +/- 154 ppm
All tests reported on this blog are from tests done for a minimum of 60 seconds each unless otherwise noted. Tests were repeated multiple times (on each component) to confirm the results. Results are science-based, replicable and accurate. All metals detected in “consumer goods” mode with the XRF instrument are listed above. If a metal was not detected it is not listed.
At 39 ppm Lead in the base clay – that is a contaminant of the substrate and not an added ingredient. Most base-clay (in ceramics from around the world) has at least some trace amount of Lead (typically within the same range as the amount found in this cup.) The Lead-free glaze is thick and well applied resulting in a finish that protects against any potential Lead leaching into the contents of the cup. I would be comfortable drinking from this cup if you served me a beverage in it while I was visiting your home.
To see more items from Cost Plus / World Market that I have tested, click here.
As always, thank you for reading and for sharing my posts.
Please let me know if you have any questions.
Tamara Rubin
#LeadSafeMama
Hello there. I recently came to realize that I may have unknowingly been ingesting heavy metals from this cup. For at least a year I have been drinking coffee out of a cracked and chipped version of one. It’s my favorite cup but today the taste of metal was so strong that I decided to investigate. I have dabbled in ceramics and vaguely recalled the heavy metal leaching dangers in clay that isn’t fired right or glazed appropriately. Anyway, I’m hoping to find answers about how much danger I’ve put myself in. How bad is it to drink coffee out of this cup if it’s cracked and chipped?