Emgee, the same thing happened to a tin full I had some years ago, but I bought some in a plastic bottle from the Midlands show a few years ago. It is still clean with no leaks.
Thanks to Mike Poole for the info, and to mechman48 for the laugh.
The nuts and threaded tube are new ones and were by my standards expensive, which is why I didn't want to try something I have never done before with them, IE solder on zinc plating.