Three Chimneys: Summer Fruit Jam

Well, actually not-quite-Three Chimneys Summer Fruit Jam. Why? The recipe actually uses a combination of five fruits: strawberries, raspberries, gooseberries, redcurrants and blackcurrants. Unfortunately, I could only get four of them. The fruit farm we went to hadn't had a very good season for gooseberries, and there were none left. We did manage to pick redcurrants and blackcurrants, and got some ready picked raspberries and strawberries. So I made up the missing gooseberry portion using the other four fruits in about the same proportion.
The one thing I was most worried about here was whether the jam would set. I know the principle of testing it - put a plate in the fridge so that it gets cold, then after the jam has been boiled for the right amount of time (this recipe said 15 minutes), drop a teaspoonful onto the plate. Allow it to cool for a bit, then push it with your finger. If it wrinkles, it's ready. So I tried. After 15 minutes, no wrinkle. Boil another few minutes, test again. Is that a wrinkle? Not sure, boil a bit longer. After a total of 25 or 30 minutes, I thought it was sort of wrinkling, and was worried about over-boiling it, so decided that was it ready to go into the jars.
So how did it turn out? I'd say not bad for my first attempt. Out of the 1kg total of fruit I made 6 small jars of jam. One of those is nearly finished, one is earmarked to go to my dad, leaving four to last until I can do it again. Next time with gooseberries.