2
I'm 95% confident that, in this case, it was nickel sulfide contaminant. I took photos of the epicenter of the shatter and zoomed in on the computer. The contaminant is pretty clear to see:
This is pretty much exactly what articles like these show: https://www.constructionspecifier.com/fully-tempered-glass-and-spontaneous-fracture/2/
Only top voted, non community-wiki answers of a minimum length are eligible
Related Tags
glass × 155windows × 28
doors × 14
shower × 14
bathroom × 12
repair × 12
adhesive × 9
mirror × 8
walls × 7
safety × 6
cleaning × 6
furniture × 6
table × 6
drill × 5
cutting × 5
insulation × 4
kitchens × 4
roof × 4
wood × 3
tile × 3
paint × 3
light × 3
cabinets × 3
patio × 3
sealing × 3