In the work bowl of a food processor, process raspberries until puréed. Using the back of a spoon, press purée through a fine-mesh sieve into a large bowl; discard solids.
Add orange zest and juice, sugar, and lemon juice, stirring until sugar is dissolved. Pour mixture into a 13x9-inch baking pan. Freeze until no liquid remains, about 4 hours, scraping frozen mixture with a fork every hour until fluffy.
Recipe by Southern Lady Magazine at https://southernladymagazine.com/raspberry-orange-granita-recipe/