Follow steps 1 through 4 of Canning Instructions, using four pint-size jars.
Pit and coarsely chop peaches, nectarines, and apricots; you should have 6 to 7 cups total.
In an 8- to 10-quart pan, combine fruit, raisins, lemon juice, butter (if using), and pectin. Bring to a rolling boil over high heat, stirring often. Stir in sugar; when mixture returns to a boil, stir for exactly 4 minutes if using MCP pectin (1 minute if using Sure-Jell or Ball Fruit Jell). Remove from heat.
Skim and discard any foam. Add rum (if using) and almonds. Stir occasionally for 5 minutes to distribute fruit and nuts.
Follow steps 5 through 11 of Canning Instructions, leaving 1/4 inch of headspace in each jar and processing jars for 5 minutes (see notes).
Note: Nutritional analysis is per tablespoon.