In a bowl, combine the balsamic vinegar, honey, olive oil, garlic, salt and pepper to create a marinade.
Place the pork chops and peach quarters in the marinade, making sure they are well coated. Marinate in the refrigerator for at least 30 minutes, ideally overnight.
Preheat grill to medium-high.
Grill pork chops for about 3-5 minutes on each side, until cooked through.
During the last few minutes of cooking, place the peach quarters and rosemary sprigs on the grill, around the pork chops. Grill until peaches are slightly tender.