Sort the raspberries and puree them in the blender. Strain through a sieve to separate the stones from the pulp.
Score peaches crosswise and scald with boiling water. Peel and puree as well except for 1 or 2 pieces.
Put the fruit in a large saucepan and bring to the boil with the washed lavender. Let it steep for approx. 2 - 3 hours. Then fish out the lavender.
Add the sugar with Gelfix and the peaches that were retained and cut into pieces and cook according to the instructions on the packet.
Tip: Do not use too much lavender so that the jam does not taste perfumed. Try after brewing and add fruit if necessary.
I specified the glasses just to put in a lot. I myself use small jars, such as for diabetic jam or vegetable spread, then there are more than 9 pieces.
You can also use fructose or other sweeteners to make diabetic jam.