Check for cracks or chips. Never saw a standard canning jar glass failure in all my canning. The only failures were when my ex MIL used regular glass jars instead of canning jars
Your pressure canner should have a tray that raises the jars off the bottom of the pot. Never place jars directly on the bottom of any pot.
Only accept used jars that have raised lettering on them (Ball, Kerr, etc). There are safe jars that don't have this feature, but you wouldn't know for sure buying them used. Always check for imperfections - chips, air bubbles, etc.Really good to know; thanks! Should I be concerned that anything used will blow the bottom off in my pot? Is there a way I can tell if a jar is weakened before I buy it?
I've used Golden Harvest in the past without any issues.Ball and Kerr brand jars here only. Same with lids, but venturing out this year with some Golden Harvest lids.
This was common early on. At some point they changed the threads to prevent regular rings from working properly to avoid liability issues.Mom and grandma always used glass mayo jars for canning jams. I still have a couple of them. If a regular lid and ring will fit, you can waterbath with it.