I'm thinking of getting a damson tree on dwarf stock this autumn, to be able to make damson jam, and damson tart to which my mother addicted me. She said leaving the stones in while cooking intensified the flavour.
The damson jam I made last year was to a simple French recipe for confiture de quetsch, adding nothing but lemon juice and demerara sugar and macerating the fruit overnight before fast-boiling in the morning. It was paradise.
The house is clanking with saved jam jars - when we run out of homemade jam we buy Folláin jam, which comes in very cute pots (but I think is only available in Ireland) and save the jars and lids.