In a large mixing bowl, combine the butter, milk, orange extract, and peppermint extract with an electric mixer or by hand until smooth. Gradually add the powdered sugar, blending thoroughly after each addition. Cover and refrigerate 4 hours or until firm.
Cover 2 or 3 large baking sheets with waxed paper. Shape the mixture into balls 1 inch in diameter. Place the balls on the waxed paper and flatten with the palms of the hand or the back of a spatula. Cover and freeze one hour, or until firm.
Cover a large counter top area with waxed paper.
In the top pan of a double boiler over hot but not boiling water, melt the chocolate candy coating and semisweet chocolate together, stirring until smooth. Using a fork or a specially designed dipping tool, dip the mints into the melted chocolate until coated. Drop the mints onto the waxed paper. Let stand until the chocolate is firm. Store in an airtight container, separating each layer with waxed paper. These mints may be refrigerated or frozen if desired.