I've been looking for a chemical-free sunblock too because my son was getting a rash on his face from sunblock. I've been using Green Babies zinc oxide sunscreen (unscented with pomegranate seed oil). This is the only one so far that does not irritate his face.
ACTIVE INGREDIENTS: Zinc Oxide 20% INACTIVE INGREDIENTS: Water, Aloe Barbadensis Leaf Juice*, Capric Caprylic Triglyceride, Sorbitan Stearate, Hydrogenated Methyl Abietate, Polyglyceryl-10 Laurate, Castor Oil, Magnesium Sulfate, Helianthus Annuus (Sunflower) Seed Oil*, Simmondsia Chinensis (Jojoba) Seed Oil*, Tocopherol, Punica Granatum (Pomegranate) Seed Oil*, Polyaminopropyl Biguanide
*Certified organic ingredient
Only drawback is the price - it's $16.99 for 3 fl. oz at Whole Foods. But I'm only using it for the face.
Also tried Neutrogena pure and free baby faces as well as Banana Boat's Natural Reflect but while okay for the body, they still irritated his face somewhat. Maybe it's the titanium dioxide that is absent in the green babies sunblock?