Combine all of the ingredients apart from the butter and rum in a large bowl and stir to combine.
Place the butter in a pan big enough to fit all of the other ingredients and melt the butter gently, don't allow it to bubble, you don't want to fry the fruit.
Tip in the dried fruit and bring up to temperature, when the sugar has melted warm the mincemeat for 10 minutes and stir regularly to stop it catching on the bottom of the pan.
While the mincemeat is cooking sterilise your jars - the easiest way to do this is to wash the jars in warm soapy water, then dry them and place them in an oven preheated to 110C Fan, leave the jars for a few minutes and then remove them from the oven and place them somewhere safe to cool down.
After 10 minutes take the pan off the heat and allow the mincemeat to cool.
When the mincemeat is no longer steaming, add the rum and stir to coat all of the fruit. spoon the mincemeat into the sterilized jars and put on the lids.
The mincemeat should keep in a cool dark place for at least two months.