bhamcurry agree Tin Cans are single use.

I do like watching American/Canadian Homesteader videos
Mainly for Carpentry and Timber building, People living in remote wide open spaces
Canning was an obvious necessity rather than a hobby.
I do have a few Mason and Kilner Jars, but they are quite expensive in the UK.
Not cost effective for BIR curry gravy at all.
As for Tin Cans, step back in time (circa 1925 home kit)

Italian Grandma water bath method is interesting
https://youtu.be/Qn_Yx3NmaNYcheers Chewy