Last summer was my first time canning. I only have plans to do tomatoes this summer & perhaps some apples(sauce, pie filling) this summer. I thought about getting some half pint jars because sometimes you want just a bit more tomatoes for what you are making & a quart or pint is more than you need. So you end up with an open jar in the fridge. Thought if I got another rack, then perhaps I could do pints & half pints in one batch. Or 2 sets of half pints in one batch. I think my pot would be big enough for that. Don't have a set plan, but dreaming about what I can do this summer, lol.

Yes to both questions - you can process the first recipe as per any conventional marmalade and you can sub blood oranges for the Seville in the second recipe. Carol

There are several kinds of breakage you might experience in canning jars. (If you can lots or over a long period it's likely you'll see all of them at one time or another.) As Dave said, thermal shock is identified by a crack that runs around the lower portion of the jar and sometimes up the side (the bottom falls out). A vertical crack that runs up the side and may "fork" is an internal pressure break. That's caused by inadequate headspace, sudden changes of temperature in a PC (forced cooling by running water over the top of the canner or removing the weight before pressure reaches zero). Impact breaks look like a windshield does when a rock hits it. I think of this one everytime someone returns canning jars clanking around in a plastic bag. It also can happen if a jar is damaged by a metal knife used to remove air bubbles or just the wear-and-tear of age such as scratching or rubbing. Carol

Pickles (the poster, not the product), hi. For reprocessing, while I have the contents dumped in the pot, I wash the jars again, and yes, new lids of course. For your situation of having a jar's worth left and wanting to start a new batch, if it's a new batch of the same thing, why not save it in a bowl and then when the second batch is ready, add the jar's worth back in, heat a few more minutes, and then fill all the jars? With jam I would just put the jar in the fridge to avoid having it set and then reheat (except with no-added-pectin jams, I guess you could leave those on low heat in a small pot on another burner while making the next batch). Actually with jam, I personally would feel comfortable doing open kettle (just letting it seal) and clearly marking that it's only for myself and that I will use it first--in which case, I would just put it in the fridge anyway. When you found mold in a jar, was it fuzzy, or was it just black stuff? Sometimes canned products will get black stuff on the lid, but it's just a dried-out or oxidized version of what's in the jar. If it was really mold, it is probably a bad seal. I had some peaches that no matter how many times I washed the outside of the jar, mold would grow along the threads. Never got inside, but sure was unappetizing (kept those for myself also). Melissa