In a small saucepan, heat berries over medium heat, covered, until softened and starting to release juices, about 5 minutes. It may take a little bit longer for fresh berries.
Once soft, use a fork or a potato masher to mash the berries until mostly smooth. Stir in the orange juice and chia seeds until combined.
Cook uncovered over low heat until slightly thickened, about 2-3 more minutes.
Remove from heat and allow jam to cool. It will thicken more as it cools. Stir again and place in an air-tight container in the refrigerator.
